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fatigue to the presence of uric acid in the blood-in fact, rather than as due to the ill-treatment by over-anxious considers a fatigued man to be in exactly the same con- mothers not content to let Nature alone in her progress dition as a gouty man. His observations, however, towards recovery. Having assumed that vaccination is seem to have been very few in number, and the analyses no protection against small-pox, the book goes on to show were all made for him by a friendly chemist. Still, it is that the only means we have of controlling the devasta. unfair to the book to regard it as a contribution to the tions of this disease is by attention to sanitary arrange advance of physiological science. It is really an excel- ments and by isolation, perhaps combined with judicious lent little account of the physiology of bodily exercise, inoculation. The latter, the book assures us, is a more and its rôle in the maintenance of health, by a medical scientific procedure than the inoculation of cow-pax practitioner. It seems to be chiefly culled from the Next, the author is very angry with Jenner for calling standard French works on general physiology, and on vaccinia, cow-pox” or “variola vaccinia." To this the physiology of movement. The author has digested stroke of dexterity by Jenner is to be attributed, says his materials well, and so produced a very readable and Prof. Crookshank, all the credit that vaccination has lucid account of his subject. For a book of its class, it is attained ; thus for a single happy thought Parliament remarkably free from mistakes, though physiologists gave Jenner £30,000 as a consequence of ħis conceit, ang might not agree with him in his account of the produc- England has been made to submit to the most tyrannica tion of breathlessness or the causation of gout.

of laws. The style is simple, and the book is well adapted for This carping at the pioneer of new knowledge, an popular use, and ought to find favour with our exercise- more especially at those forecasts of his which necessarik loving countrymen.

E. H. S. could only be verified by the lapse of time, is certain

not calculated to shake the faith of those who now full BoilersMarine and Land. By Thomas W. Traill, comprehend not only the immense value of vaccination.

F.E.R.N., M.Inst.C.E. Second Edition. (London : but also the small amount of mischief which it has ever Charles Griffin and Co., 1890.)

done. This volume is a second edition of a work noticed in The best that can be said for Prof. Crookshank's work these columns last year. It was then a pleasure to ex- is that it is well published. The printing is bold and press the opinion that the work would be useful to all clear, and the lithographs, such as they are, wel connected with this particular branch of mechanical reproduced. engineering. The author has found it necessary to extend

Vol. ii. contains reproductions of original papers, mos the tables of scantlings, &c., from 160 to 200 pounds if not all of which are out of print, and cannot not be pressure per square inch. 'This in itself is sufficient obtained except at fancy prices. evidence of the continued increase of steam pressures Had Prof. Crookshank been satisfied with editing these, used in marine and stationary engines-probably the only and had he refrained from expressing his opinions, we practicable direction in which greater economy of fuel is to should have been grateful to him. The book does no be obtained. These increased steam pressures have also pretend to be a practical work on the subject of which it the advantage of diminishing the gross weight of machinery treats ; and for the rest it might have been compiled by on board ship.

the average anti-vaccinator,

ROBERT CORY. The greater use made of mild steel by engineers generally is interesting, considering the fight the steel manufacturers had a few years ago to get it used at all in

LETTERS TO THE EDITOR. place of iron for many purposes:

Mr. Traill observes that,“ notwithstanding the peculiarities of mild steel, it (The Editor does not hold himself responsible for opinions of is a material which may be used with safety and advan

pressed by his correspondents. Neither can he underla.

to relurn, or lo correspond with the writers of, rejate tage, if proper precautions be taken and due consideration

manuscripts intended for this or any other part of NATURE given to these peculiarities ; possibly it has fewer in

No notice is taken of anonymous communications. ] firmities than iron ; and there can be no doubt that it is a better and more serviceable material for general use in The Transmission of Acquired Characters, the construction of boilers. This is the experience of

and Panmixia. most engineers intimate with the general behaviour of I SUPPOSE Chat a correspondent has no claim to limit the the material when being worked up into boilers and other scope of discussion in such a journal as Nature. At the constructions. To the many tests and safeguards specified same time I feel it to be a rather severe burden when I am called to prevent the use of a brittle and bad steel in any erection upon to expound, in answer to one letter after another, the meres is due the present excellence of this material, nor should common places of ihe subject under discussion, and to retail 1 they now be in any way relaxed, for to accept material, this place the substance of books like Weismann's " Esay, either iron or steel, on any particular brand is a mistake.

and Wallace's “Darwinism ” (10 which the altention of you The general utility of the work has been increased by

readers has been already drawn by reviews), not to mention the the addition of other matter and tables. The volume “Philosophie Zologique" and the “Origin of Species." }

seems to me that there might be interest and profit in openior cannot fail to be of very great use to engineers. It is

your columns to the statement of newly observed cases when nicely printed, got up in a handy size, and strongly yet

seem to tell in favour of either the Lamarckian or the antipliably bound.

N. J. L.

Lamarckian theories, or to novel criticisms of any cases which The History and Pathology of Vaccination. Edited by citation of familiar exploded cases,” and the reiteration of

have already been discussed elsewhere ; but surely the repeated Edgar M. Crookshank, M.B. Two Vols. (London:

arguments and beliefs which have long since received alieution H. K. Lewis, 1889.)

is not fair to the writers who have dealt with these cases and these The arguments adopted in this work belong to a mental arguments in admirable treatises which are well known (I am attitude identical with that displayed by anti-vaccinators happy to think) to nearly all serious students of these questions in their clamorous treatment of the subject. They are

When I saw the distinguished name of Mr. Herberi Spencer sophistical from beginning to end, and even as a book of

at the end of a letter in your issue of March 6, I anticipated reference the volumes are not without drawbacks.

some real contribution to the discussion as to whether acquired

characters are transmitted or not. Mr. Spencer some few yet Firstly, the argument is that cow-pox is to be regarded

ago expounded his convictions in favour of Lamarck in one as akin to syphilis rather than to small-pox, and that

of the monthly reviews. His present lelter is pot only ditherefore cow-pox is no protection against small-pox. On appointing, but is unfortunately likely to mislead the una this hypothesis ulcerated arms sometimes occurring after formed. Mr. Spencer states what we all know, viz. that Mi vaccination are to be regarded as reversions to type, Darwin considered that the effects of habit and of ase and disuse are transmitted from the affected generation to its off- due to inherited mutilation, though he supposes they may have spring. He refers by chapter and page to the instances which become deficient through disuse. He regards the defective Mr. Darwin considered as examples of the transmission of the eyes of cave-animals as due to the inheritance of the effects of effects of habit or of use and disuse. He then says : "Clearly disuse. I can scarcely doubt that, had it occurred to him, he the first thing to be done by those who deny the inheritance of would have preferred an explanation similar to that given by acquired characters is to show that the evidence Mr. Darwin him of the wingless island beetles, viz. that a natural selection has furnished by these numerous instances is all worthless.” I of animals with defective eyes takes place in a cave; since entirely disagree with this way of putting the matter. It is not ultimately only those remain in a cave and breed in it which, secessary to show that anything Mr. Darwin wrote was “worth. in the course of their wanderings, are unable to see the faint less," but it is necessary to show that certain facts cited by Mr. light which penetrates to a great distance from the mouth, and Darwin admit of another interpretation or explanation than that must guide all those but the congenitally blind or weak-sighted which he gave to them. Naturally those who have taken up to the exterior. The defective eyes of moles are ascribed by the anti-Lamarckian position have done long ago what Mr. him not merely to disuse but to the selective action of inflamHerbert Spencer says is the first thing for them to do. Of mation. The case of the silkworm caterpillars with defective course the cases cited by Darwin were the first to be dealt with. instincts (which is one of those given by Mr. Spencer) does not It is extremely unfortunate that Mr. Spencer has not come appear to me to bear on the present question. Of acquired across the work in which this is done. Otherwise, instead of a characters, other than those due to disuse, Mr. Darwin accepts well-meant direction from Mr. Spencer as to what we ought to very few as being transmitted. He accepts the statements of do, we might have the advantage of reading what he has to say Brown-Séquard as to the transmission of the effects of mutilaafter considering what has been done. It is seven years since tions of guinea-pigs only so far as to “make us cautious in Prof. Weismann published his essay on heredity ; last spring denying such transmission." He regards the dislocation of this and other essays appeared in English under the auspices of the eye of flat-fishes as due to the inheritance in successive the Clarendon Press. In that particular essay Darwin's cases generations of an increasing displacement caused by muscular are dealt with at length. Am I to reproduce Prof, Weismann's effort. Besides these two instances noted by Mr. Spencer) essay or a précis of it in this letter? Will not Mr. Spencer there is one other prominent passage in which Darwin asserts his and others who are interested in these matters read Weismann's belief in the inheritance of an acquired character which is not “Essays "? I think that those who will take the trouble to do merely the result of disuse. I am anxious to separate those cases so will see that Mr. Spencer's injunction was superfluous. which Darwin speaks of as “due to the effects of disuse,”

It is, however, apart from other branches of the question, for a reason which will appear below. The additional passage important that a correct appreciation of Mr. Darwin's position not noted by Mr. Spencer is this (“ Origin of Species,” p. 206, in this matter of the "transmission of acquired characters" sixth edition):-"If we suppose any habitual action to become should be arrived at. Mr. Herbert Spencer's letter is, I think, inherited-and it can be shown that this does sometimes happen likely to produce an erroneous conception on this matter. We - then the resemblance between what originally was a habit and koow from his letters published since his death that Darwin an instinct becomes so close as not to be distinguished. If held the "Philosophie Zoologique” to be " veritable rubbish”— Mozart, instead of playing the pianoforte at three years' old with "extremely poor; I got not a fact nor an idea from it.” The wonderfully little practice, had played a tune with no practice at Bolion that his own view was a modification of Lamarck's all, he might be truly said to have done so instinctively. But it appeared to Darwin absurd. The “obvious view

was pro

would be a serious error to suppose that the greater number of pounded by Lamarck, he says, “tbat if species were not created instincts have been acquired by habit in one generation and then separately they must have descended from other species, and I transmitted by inheritance to succeeding generations. It can can see nothing else in common between the Origin' and be clearly shown that the most wonderful instincts with which Lamarck." This was Mr. Darwin's attitude of mind to we are acquainted-namely, those of the hive bee and of many Lamarck's theory, and the cases in which he attributes import. ants-could not possibly have been acquired by habit.” ance to the effects of use and of disuse, and to acquired habit, The cases of the epileptic guinea-pigs, the eyes of flat-fishes, and consequently to the Lamarckian principle of the trans- and of some acquired habits, have been discussed by Weismann bussion of acquired characters, are clearly to be regarded as and by Wallace. I will not now allude further to those classes Cuncessions or admissions on his part, given with increasing of cases. But I am anxious to draw attention to the special generosity in the later editions of ihe ** Origin"; but always subject of the “effects of disuse as set forth by Mr. Darwin. treated as of quite subordinate importance. It is not going too This phrase is not only used by him in regard to special infar to say that Mr. Darwin never troubled himself very much stances, but, in treating of the large subject of rudimentary with the question as to whether acquired characters are trans- organs, he frequently refers to the "effects of disuse." He mitted or not. It was the object of his works to show that the says, “It appears probable that disuse has been the main agent main effective principle in the origin of species is the natural in rendering organs rudimentary "" Origin," p. 401). selection in the struggle for existence of congenital characters. Now I am anxious to point out three things in regard to the He explicitly states that he believes other causes to be at work ; "effects of disuse.” (i) There are other possible effects of une of which at least, viz. sexual selection, he himself investi- disuse of an organ than the dwindling of that organ in one gatot ar length. It must be remembered that no evolutionist generation, and ihe inheritance of the organ in a diminished size in Darwin's life-time had prominently challenged the truth of the by the next generation. (2) The anti-Lamarckians attribute a Lamarckian assumption that acquired characters are transmitted. very great effect to disuse, although they do not attribute to it For Darwin it was sufficient to show that, granting such a the particular result which Lamarck did. (3) The particular process to take place, it would not account for much ; he way in which, according to the anti-Lamarckians, disuse acts so was content to accept it as a subordinate factor. His view is as to lead to the dwindling or complete loss of the dicused organ best stated in his own words in the "Origin of Species": has been called by Weismann by a convenient name—"panmixia." “On the whole we may conclude that habit, or use and disuse, The doctrine of panmixia is already indicated by Darwin him. have, in some cases, played a considerable part in the modi- self, and in view of this fact we must suppose that, when he fication of the constitution and structure.”

attributed the loss or dwindling of an organ to “disuse” or the Whilst it is true that Mr. Darwin in various parts of his "effects of disuse,” he did not necessarily (though probably he works alludes to cases which he interprets as due to the trans- frequently did) refer to the Lamarckian modus operandi of mission of characters acquired by parents through habit, use, or disuse, but may very well have had in mind the results which disuse, it is obvious, when we read what he has to say in each are a'tributed to disuse by the anti-Lamarckian doctrine of case (as in the examples cited by Mr. Herbert Spencer), that pannixia. he preferred, where it occurred to him another interpretation. The doctrine of panmixia is this. When there is no longer, Thus, after referring to the wings of the logger-headed duck owing to changed conditions of life, any use for an organ, it and the domestic Aylesbury duck as dwindled by the trans- will cease to be the subject of natural selection. Consequently dission in successive generations of the effects of disuse, he all possible variations of the organ will have (so far as the now interposes his own explanation by natural selection of the wing. lapsed use of the organ is concerned) an equal chance. Amongst less beetles of Madeira, prefaced by the words: “In some cases the possible variations there will be the variation in the direction we might easily put down to disuse modifications of structure of increased size, and its exact complement-the variation in the which are wholly or mainly due to natural selection.” He direction of diminished size. Prof. Weismann has stated briefly refuses to regard the defective anterior tarsi of dung-beetles as that this equal survival of all possible variations must lead to the

dwindling and ultimate loss of the organ. I would, however, Probably your readers will be as much astonished as I was venture to supplement what he has said by the following : viz., when they read the extracts I have above given from the "Origius given the state of panmixia, it is apparent that variations in the of Species " by the side of Mr. Romanes's letter. direction of excessive size will be injurious-both as taxing After dismissing Mr. Darwin, Mr. Romanes proceesls to say: the nutriment of the organism, and often as mechanical en- “ In this connection, however, it requires to be stated that the cumbrance. On the other hand, variations in the direction idea first of all occurred to myself, unfortunately just after the of greatly diminished size will be advantageous, as causing appearance of his last edition of the Origin of Species.'". a diminished tax on the resources of the organism. Now Now, inasmuch as the idea in question is (as I have shown it is a demonstrable fact that excessive variations in both direc-above) formulated in the last edition of the “Origin of Species," tions do naturally though rarely occur-probably more often than I confess that I do not think it requires to be stated tha! the is supposed, since we do not see all the young born. If the varia- idea occurred to Mr. Romanes shortly after the publication of tions in the direction of excessive diminution of a useless organ that work. What more natural? The idea occurred to be (as, for instance, tailless cats or hornless sheep) survive as being also shortly after the passages above quoted from Mr. Darwin less taxed-whilst the complementary variations in the direction were published. It certainly never appeared to me "anfor of excessive size tend in the struggle to die without reproducing, tunate" that this was the case, and I cannot see where the mis owing to their awkwardness and their relatively greater burden fortune comes in in regard to Mr. Romanes. As soon as the in life-then it is clear that panmixia may lead rapidly to the matter had taken root in his mind, Mr. Romanes published in dwindling and eventual extinction of a disused organ without NATURE, March 12, April 7, and July 2, 1874, an exposition or any transmission of acquired parental character. The fact that the importance of the principle of cessation of selection w there is no use for an organ-or, in other words, the "effect of commentary upon a letter by Mr. Darwin himself (NATUEL, disuse "-is that the congenitally small varieties of the organ vol. viii. pp. 432, 505) in which Mr. Darwin had suggested that, survive, and are even favoured in the struggle for existence. with organisms subjected to unfavourable conditions, all the

Whilst Weismann has the merit of having insisted on a form of parts would tend towards reduction. Mr. Darwin, with fuis usua) his doctrine as the effective reply to those who argue in favour of kindly manner towards the suggestions of a young writer, gites et Lamarck's theory of the transmission of acquired qualities from p. 309 of vol. ii. of “ Animals and Plants under Domestication instances of " disuse,” it is yet the fact that Mr. Darwin him. (second edition), Mr. Romanes's view, “as far as it can be giver self recognized and formulated the doctrine of panmixia in the in a few words. The view, as it there appears in Mr. Darvio's last (sixtă) edition of the “Origin of Species," published in 1872 ; words, is certainly not the same as that which dir. Ramaze iz and he even went further than Weismann, for he associated the expounded in NATURE of March 13, 1890 (p. 437), and Eace i principle of the economy of material with the principle of the represents what Mr. Darwin had been able to gaiber free: No cessation of selection. It is therefore, it seems to me, not at all Romanes's letters to NATURE of 1874, it is not at all surprisa improbable that when Darwin refers, here and there throughout that Mr. Darwin did not recognize any resemblance between his works, to a reduced or rudimentary condition of an organ as and his own statement, viz. that "the materials forming “due to disuse," or "explained by the effects of disuse," he does part, if not useful to the possessor, are saved as far as possible

, not necessarily mean such effects as the Lamarckian second law thus “rendering a useless part rudimentary." Whether thu asserted and assumed (though often he does appear to mean such); | is, or was, Mr. Romanes's view or not, it is Darwin's, and is like but he may mean, and probably had in his mind, the effects esserce of the anti-Lamarckian view of the effects of disuse. of disuse as worked out through panmixia and economy of March 15.

E. RAY LANKESTER, growth.

The passages in Darwin which seem to me to have been missed or neglected by those who think panmixia altogether a

Exact Thermometry. new idea are as follows :

SHORTLY after the publication of my second letter on this (1) “If under changed conditions of life a structure before subject (NATURE, January 23, p. 271) I received a letter from useful, becomes less useful, its diminution will be savoured M. Guillaume, who very kindly called my attention to for it will profit the individual not to have its nutriment by Prof. J. M. Crafts (Compies rendus, xci. p. 370), in which wasted in building up a useless structure.” After an example the “plastic theory” is discussed. Prof. Crafts states that he in point from the group of the Cirripedia, Darwin con- has subjected thermometers to prolonged heating at 353* C.

, ttinues : “Thus, as I believe, natural selection will tend in the under various conditions as regards pressure, the intermal pre long run to reduce any part of the organization as soon as it sure being in many cases considerably greater than the cutertaal. becomes, through changed habits, superfluous, without by any but that there was invariably a rise of the zero-point. The er means causing some other part to be largely developed in a periments were carried out in very much the same manners corresponding degree” (“Origin of Species," sixth edition, that described in my first letter (NATURE, December 19, 1890

p. 152), and had I known at the time of the earlier work of (2) “Organs, originally formed by the aid of natural selection, Prof. Crafts, I should of course have referred to it. Prol. Crafts when rendered useless, may well be variable, for their variations also describes and quotes experiments with air-thermometers

no longer be checked by natural selection. . . . It is the temperature in one determination by Regnault being s bigh scarcely possible that disuse can go on producing any further as 511°C., and the internal greater than the external pressure : effect after the organ has once been rendered functionless. in every case the bulb diminished in volume. From these re Some additional explanation is here requisite, which I cannot sults, Prof. Crafts concludes that it is not proved that pressure give. If, for instance, it could be proved that every part of the plays any part in the contraction of the glass. organization tends to vary in a greater degree towards diminu- My experiments can therefore be regarded as little more than tion than towards augmentation of size, then we should be able confirmatory of the earlier work of Prof. Crafts and others, ba to understand how an organ which has become useless would as such it may be worth while to give the results. The method be rendered, independently of the effects of disuse, rudimentary, adopted was fully described in my first letter, and it is therefore and would at last be wholly suppressed; for the variations only necessary to repeat that in thermometer A the esterna towards diminished size would no longer be checked by natural pressure exceeded the interpal, while in thermometer C there selection. The principle of the economy of growth explained in was considerable internal pressure, but no external. According a former chapter [cited in quotation No. 1), by which the to the plastic theory, therefore, the zero-point of A should have materials forming any part, if not useful to the possessor, are risen, while that of C should have fallen. The results queviash saved as far as possible, will perhaps come into play in rendering described were regarded as insufficient by Prof. Mills

, and ! a useless part rudimentary” (“Origin of Species," sixth edition, have therefore continued the heating for a much longer time PP. 401-402).

I have also made similar experiments with two other thermo I had written thus far, and intended to finish this letter by meters belonging to the same batch, at a temperature of about asking if the anti-Lamarckians are not really carrying out the 356°, the thermometers being heated in the vapour of boiling spirit of Darwin's doctrines, although not the absolute letter, mercury. During the first three hours, the two thermometers when I received your issue of March 13, containing a long letter a and ó were treated in precisely the same mannes, as regando from Mr. George Romanes, headed “Panmixia.” In that letter pressure, as A and C, and it will be seen that the zero ponto Mr. Romanes, whilst amending (as I have done above) Prof. b showed a slightly greater rise than that of a. Alterwards, air Weismann's statement of the principle of panmixia, makes the was admitted into thermometer a, so that there was an excess of definite assertion that "it is remarkably strange that this prin- internal over external pressure in both thermometers, but the ciple should have been overlooked by Mr. Darwin."

excess was greater by one atmosphere in 6 than in a

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The results obtained are given in the following table :

I may also mention that M. Guillaume has informed me that

M. Tonnelot has heated several thermometers to 450°, and that, Temperature 280°.

notwithstanding a considerable internal pressure, a rise of the Total Duration Zero. Rise

Z:ro

Rise Mean zero-point was observed in every case. of point of point

All these results seem to lead unmistakably to the conclusion cach of A.

of C.

zero per hours. heating

hour.

that pressure has little or no effect on the rise of the zero-point.

Three questions remain to be discussed — 0'15

(1) Would the total rise of the zero-point be different if two 2 095 o'35 ... +0'3 0-4 0*187 similar thermometers were subjected to sufficiently prolonged 7'S 55 ... 13

0.8 II 0:8 0'145 heating at different temperatures ? At first sight, it would cer12 4'5 ... 20 07 1.8

oo7 0'156 tainly appear that at 356° the total rise with my thermometers 17 5 23 0'3 2'05 0'25 0'055 must be greater than at 280°, but I do not feel satisfied that the 22'5... 55 ... 26

0-3 2'15 ...

o'r 0'036 proof is sufficient. If we map the observations of zero-point 29 6.5 ... 295

0*35 2'5

0:35 0'054 against the time of heating, curves are obtained which appear 35

6

3:15 0'2 28 0-3 O'042 as if they might become horizontal after a few weeks or, pos51 4'1 0.95

3'95

I'15 O'020 sibly, months; but if, instead of the actual times, we take their 133 47

07 49 0'95 O'018 logarithms—as in the diagram-as abscissæ, there is no appear. 201 68 5'25 0:45 55

0.6 O'008 ance of an approach to the final state at either temperature. 369 168 6:5 1'25

68

13
. O'008

But while at 356° the curve has become almost a straight line,
Temperature 356o.

at 280° there appears to be an increasing tendency towards the

vertical direction. I do not for a moment argue that the curves 6

indicate that the maximum rise would be the same at both tem04

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peratures if the experiments were carried on for a sufficiently

long time ; but, at the same time, I do not think that they 3 3

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afford any convincing proof that the total rise would be different. 2'0 81

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The results merely tend to increase my scepticism as to the 12'5. 6'5 ... 10-3

10'35 2'25 0*350

value of the determination of the maximum rise at oo obtained 15 295 ... 10°95 0065 III 0°75 0'280

by extrapolation of the curve constructed from observations at 66 51 ...161 5'15 16'1 5'0

0100

that temperature. It does not appear to me that it would be 113 47 ... 18-45 2-35 18.3

0'048 181 68

justifiable to extrapolate these curves at all, and I am afraid that ... 201 20'0 17 0'025

they do not throw much light on the total rise of zero-point at 05-5... 24'5 ... 2075 0 65 20.6 0.6 0'025 231'5... 16

either temperature. Very much more prolonged heating would ...20°9 0:15 20*7

O'008
O'I

be necessary before arriving at a definite conclusion.
292
70“5 ...218 0-9 217 IO 0'013

(2) With regard to the causes of the contraction of the bulb, The last result at 356° is a little uncertain, owing to a breakage I have no hesitation in admitting that—as shown by M. Guil

. of the apparatus.

laume—the removal of the condition of strain caused by the

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mnote rapid cooling of the outer parts of the glass, is insufficient to account for the results. No doubt we must also take into

(3) Lastly, there is the question raised by Mr. Tomlinson, as

to whether repeated heating and cooling between wide limits of eing the molecules Esom Assuming ahes position of greatest longed heating at the higher temperature

. The points represulphur of the monoclinic or the more stable rhombic form de same

constructed from them, and do not seem to indicate any noticewhich solidification takes place. That able difference in the effect of long or short heating. The results besides these two does not at present can hardly, however, be regarded as decisive.

University College, Bristol, March 1, SYDNEY YOUNG.

pends on the rate at there are other causes appear to me to be proved.

carcases.

Foreign Substances attached to Crabs.

group to which he gives the very convenient name SINCE Hyas is one of the most abundant Crustaceans found cryptic.” Animals which trust rather to the offensive than a off the east coast of Scotland, Mr. Holt must adduce consider- the inconspicuous character of the foreign bodies with wbut ably more than two instances before it can be admitted that the

they associate themselves he terms "allosematic” (onna, a attachment of Simple Ascidians to this crab is at all a usual

sign). occurrence. If it is, I should still be anxious to inquire whether

It is obvious that the allosematic method of protection is 2 the crab does not-in spite of the apparent difficulty of the

but perfect, since it is largely free from the loss due to capra operation-place the Ascidians upon its back with its own nip

mental tasting attendant upon the method of a purely wartig pers. I may cite Gosse's well-known experiment with Pagurus appearance (“autosematic”).

WALTER GARSTY6. prideau.rii and Adamsia palliata, described in his “Year at Plymouth, March 21. ihe Shore," for the purpose of analogy. But Mr. Holt will find a case, probably quite similar to that which he mentions, in

Sea-bird Shooting. Bell's “Stalk-eyed Crustacea.” Two specimens of Hyas araneus were found with oysters attached to their backs, that on the Is it not time that something more was done to stop the larger crab being three inches in length, and five or six years wholesale slaughter of our sea-birds ? During the past wee old, probably a much more “serious incubus” than Mr. Holt's the havoc has been terrible, and unless some restraints in Tunicates. The crab's carapace was but two and a quarter we may expect before long to find our shores desuded a inches in length,

Hence, despite the “world of weight upon white wings. When the birds had no value, there was a la its shoulders, Mr. Thompson concluded that “the presence of though a wide one, to their destruction, becagse oé the area this oyster affords interesting evidence that the Hyas lived killing them ; but recently a large demand has sprung uria several years after attaining its full growth.” Probably the their skins, and an organized traffic is now carried on in Lİ larvæ of the oysters, and of the Ascidians also, happened to alight upon the crabs at the end of their free-swimming The shooter gets from threepence to sixpence per bird from th: existence, although six or seven years seems to me to be a amateur dealer, and for the sake of this paltry sun (surely the remarkably long age for a Hyas.

birds are worth more to us alive than this!) there is not a Barnacles upon the backs of Maia, Carcinus, &c., are also sporting lounger on the coast who can possess himself ní a şta due to the same, as it were, accidental cause.

who does not kill every bird which can be reached either fra But, whatever the explanation, these exceptional cases do not the shore or from a boat. The gulls are pursusi, I am to. alter the fact that the foreign bodies found upon Hyas are usually even as far as the Dogger Bank. fixed there by the crab itself. The specimens I have seen have The beautiful kittiwake is the greatest sufferer. One clit been covered with fragments-not living colonies-of Algæ, dealers boasted to me the other day that he had passed "2354 Hydroids and Polyzoa, which are fastened by the hairs of the ten than nine thousand dead birds through his hands t"> crab's carapace and legs exactly as in Stenorhynchus, and in season, chiefly kittiwakes." He added that he had got so this crab the process of attachment has been frequently observed carcases in one batch from one sportsman. here and accurately recorded.

From inquiries, I judge that this person's trade repracois At the same time I by no means hold that the two groups about one-third of the dead birds which have been sent away frou which were dehned in my previous letter are absolutely marked our little town this season. I know the traffic is carried on a off from one another. The hermit crabs make use of both other points, and no doubt this is but an example of what u methods of protection. Bits of Sponges may frequently be seen going on all round our coast. When we consider that the re upon the carapace of Maia, Stenorhynchus, and Inachus, and I cases which can be secured represent only a fraction of the birds have occasionally found colonies of Leptoclinum and Didemnum killed or injured, we gain some idea of the extent of the upon both Maia and Inachus. In these cases the inconspicuous chief. Indeed, during the past month it has been passible to appearance is not lost, but the attachment of small Sponges and take a long walk along our shore without seeing a single xa Didemnids is probably an additional protection against the gull. Who wishes to see a blank seascape? numerous night-feeding fishes, which hunt their prey by the Now, surely, we all have equal rights in these graceful hıriti. senses of smell and touch.

and the numerous class who love to see them alive deserve As to the inedibility of Tunicata, I did not-as Mr. Holt as much consideration as the mischievous minority whose plesstates--"assume" it. I have experimentally found it to be a sure it is to destroy them! It is not as though these biler sact (as I stated in my letter) that the odour and taste of Tuni. were worthy persons, compelled to a cruel employment for cata, and especially Compound Tunicata," are almost invariably their daily bread: they are, on the contrary, nearly all ar a sufficient to prevent fishes from eating them. Exceptions do class who deserve no sympathy-of a comforiable class wa, i not disprove the rule, and it is quite possible that Pelonaia is verily believe, would shoot their next-door neighboars the not distastesul. But this is not established by a few specimens could do so with impunity, and could dispose of the chicas having been taken on one or two occasions from the stomachs of Just imagine the new variety of " sport” which use a ib: Cod, Haddock, and Dab; and although Mr. Holt quotes Prof. described to me not long ago! He said you wald aich McIntosh as speaking of the “

" abundant occurrence of Molgula gulls at sea by baiting a floating fishing-line with liver, ani arenosa in the stomachs of Cod and Haddock, he will find upon this way, though you did not get quite so many as with a gun, reading Prof. McIntosh's words again, that they are open to a you had far better fun, especially from the killiwakes, as they different interpretation,

are wonderfully game," and, when they feel the hook. In my previous letter I omitted to mention that a species of " flacker about and scream like a child”! hermit crab also, Eupagurus lucasii, takes advantage (regu- Is it too much to ask that our Legislature, which has spent larly?) of the distastefulness of Compound Ascidians. Mr. much time in the past on laws in the interests of the so-calle. Harmer has, with much kindness, examined for me a specimen preservers" of game, will do something, and that speedily, in the in the Cambridge Museum. The crab inhabits a univalve which interests of those who would fain be truly preservers of ite som is covered with Distaplia magnilaria.

birds ? At least they should extend the protection afforded to Mr. Holt's statenient that “ Actinin mesembryanthemum is "game” to these noble birds, and order that those who shout certainly a favourite food of the Cod” is so astonishing that I them shall pay a heavy license for their despicahle sport, and hope he will adduce the evidence for his assertion. Mr. Brook those who deal in the dead carcases a still heavier. had not found this to be so when he reported upon the food of And nothing in this matter must be left to local authoritis this fish for the Scottish Fishery Board, and indeed only the In seaside places self.interest vitiates the sentiment on this que youngest Cod ever frequent the vidal waters to which A. mesem. tion. The fisherman finds it easier to earn money by letting hu bryanthena

1.um is confined. Further, although Pagurus bern- boat to the “sportsman" than by his legitimate producuve hardus, when not associated with an Anemone, is very frequently dustry ; the tradesman fears to lose these men's custom ; and the found in the stomachs of Cod and Haddock, I do not know a gentry, mostly supporters of " sport,” are perhaps not sorry 10 single instance of iis having been found in the stomachs of the have such an excellent safety valve for guns which might other same fish when associated with one.

wise poach on their preserves ; and besides, there is in Yorksture 1 am informed by Mr. Poulton that, in a work which is shortly a semi-political aspect to the matter. Thus it has happened that to appear, he has included such animals as Stenorhynchus and of late years the clause in the (so far as it goes) excellent Sea. Caildis worms, which disguise their appearance with foreign birds Preservation Act” of 1869, which permits a lengthening bodies simply in order to escape identification by enemies, in a of the close time under certain conditions, has been redderex

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