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EDWARD STANFORD'S STANDARD GEOLOGICAL WORKS.

STANFORD'S GEOLOGICAL
ATLAS OF GREAT BRITAIN.

WITH PLATES OF CHARACTERISTIC FOSSILS.
By HORACE B. WOODWARD, F.R.S., F.G.S.
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THURSDAY, OCTOBER 18, 1906.

In referring to Darwin's “ Cross- and SelfFertilisation,” Knuth speaks of the paucity of the experiments on crosses between flowers on the same

plant, but he neglects to mention what Darwin FLORAL BIOLOGY.

thought the chief outcome of his work—the fact that Handbook of Flower Pollination based upon Hermann crosses between individuals grown under identical

Müller's work The Fertilisation of Flowers by conditions fail to give vigour to the offspring; and Insects.By Dr. Paul Knuth. Translated by this is a result that includes the effect of crosses J. R. Ainsworth Davis, M.A. Vol. i. Introduc

between flowers on the same plant. tion and Literature. Pp. xix +382; illustrated. The need of a more generalised introduction to (Oxford : At the Clarendon Press, 1906.) Price 18s.

floral biology was not so obvious to us in reading net.

Knuth's book in German, but those who read it as THE HE Clarendon Press is to be congratulated on the an English text-book, presumably intended for uniappearance of the first volume of what is a

versity students, and who know the standard of serious undertaking-the translation of a German knowledge which such readers bring to the study, book in five volumes and nearly 3000 pages.

will probably form a similar opinion. Hermann Müller's book “Die Befruchtung der In the pages devoted to the history of the subject Blumen " appeared thirty-three years ago, and D'Arcy a full account is given of the various ways of classifyThompson's translation, published in 1883, has long ing flowers from a biological point of view. Here we been out of print. English readers will therefore find Hildebrand's and Axell's systems, of which the welcome the present work, incorporating as it does second is not generally accessible to English readers, the great mass of research on floral biology which being written in Swedish. Here, too, is Delpino's has been carried out in recent years.

interesting arrangement of typical Aoral mechanisms The book appears under favourable conditions, into classes. Thus class iii., made up of flowers which since the author--a recognised authority on the sub- are visited by insects crawling into the tubular ject_has been able to come to an arrangement with corolla, contains the types named after the genera H. Müller's representatives by which he is allowed Datura, Digitalis, Campanula, &c. In class vii. we to make use of all that naturalist's writings and find one of the instances of the awkward translations admirable illustrations.

which occur here and there in the English edition. The chief feature in which it differs from Müller's The mechanism of Genista, Ulex, &c., is named by books is the prominence given to the statistical | Delpino “ Forma a scatto," and this is rendered by method of studying the visits of insects. This sub- “ tension form,” which has none of the appropriateject has received especial attention of late from

ness of the original and does not direct attention to MacLeod, Verhoeff, Loew, Willis, Burkill, and others. the explosion which is so characteristic of the type. It was a department of study to which the author de

In other cases the translator is a little too literal. voted much time, and in consequence his book con- What service is it to an English reader to find tains perhaps more on this subject than most readers Hymenoptera described as membrane-winged insects, require.

or Diptera as two-winged ? It is, as Prof. Balfour says in his preface, an Under the heading “ Autogamy a list is given of encyclopædic work, and it has some of the defects of all known instances of self-sterility; this, together its qualities. It is admirable as a book of reference, with the corresponding lists of heterostyled and and will be of great value to anyone desirous of cleistogamic plants, forms a useful feature in the extending his knowledge of the subject; but we con- book. Again, in relation to cleistogamy, we are glad fess to missing what we expect in the introductory to see a refutation of some of the supposed instances volume of a handbook, namely, a broad treatment of of perpetual and unavoidable self-fertilisation, such the subject such as is needed to introduce a student

as the case of Juncus bufonius and of Salvia cleistoto a detailed account of flower-pollination. There is gama. no effective discussion of what lies at the root of

A good deal of space is given to the various classifithe whole science of floral biology, namely, that cations of flowers according to their mode of fertilfertilisation at any price is the primary necessity, isation and the type of insect visitors. The bestwhile cross-fertilisation is a secondary need. From known system is that of H. Müller, who divided this standpoint the arrangements of the sexes in them into flowers visited for pollen only, flowers with plants become comprehensible as compromises between exposed nectar, with concealed nectar, those adapted the extreme cases of cleistogamy and diæciousness. to the visits of bees, Lepidoptera, &c. These classes In one case fertilisation is assured, while cross- are known by the symbols Po, A, B, H, F, &c. fertilisation is impossible; in the other fertilisation Knuth propounded a more elaborate classification for is not a certainty, but if it occurs it implies of which he had good reasons; but why the translator necessity a

between two individuals. Nor, has altered the symbols so as to suggest the English again, is the point of geitonogamy made clear, equivalents of the class-names we cannot understand. namely, that if pollen is brought from a separate Thus, instead of keeping Kl for " small-insect Mower there is at least a chance that it may come flowers," he gives Sm as the symbol. This, except from another plant.

on general principles, is no great matter; but when

CROSS

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we find the familiar F which stood for lepidopterid

SINGLE-PHASE COMMUTATOR JOTORS. flowers applied to those fitted to the visits of Diptera

By F. Punga. we have ground for complaint. The same is true of Single-phase Commutator Motors. the introduction of new symbols for the well-known

Translated from the German by R. F. Looser. A, AB, and B. Surely English standards are suffici

Pp. xvi + 187. (London : Whittaker and Co., 1900.) ently different from those in use on the Continent

Price 4s. 6d. net. without our needlessly multiplying instances. RECENT advances in the application of single

The discussion which follows on the different phase alternating currents classes of flowers forms one of the most interesting have given rise to a large volume of literature dealing parts of the volume. Thus we get Knuth's curious chiefly with the motors employed. The possibility of observations on the proportion of anemophilous plants working direct-current motors with alternating cur. on the wind-beaten Halligen Islands in the North rents is by no means new, but it is only within the Sea, where they form 47 per cent of the flora, whereas last few years that the principles of good design have on the mainland the percentage is 21.3-a case which become sufficiently well known to enable such work. may remind us of the wingless, insects of Madeira. ing to be made a commercial success. Then, again, we have details of flowers fertilised by It was perhaps inevitable that a large part of the bats, birds, slugs, and snails which we think are literature devoted to this subject should be somewhat here put together for the first time in English. There academic; in any new departure of this kind the is also a discussion of some interest on flowers which experimental work which forms the basis of progress to our eyes are inconspicuous, but which neverthe- is in the hands of manufacturers, to whose interest it less attract many visitors. Further on is a good is that the information so obtained should not be made account of the well-known methods of fertilisation in public. It is, therefore, all the more interesting to the yucca and the fig.

examine a book which is evidently written for the l'nder pollen flowers, i.e. those visited for the sake practical man. In such a book circle diagrams should of their pollen, the author makes what seems to us occupy a subordinate position, and attention should an unnecessary blot in system classification. be directed to the question of proportions that may be Thus Sarothamnus scoparius, Genista tinctoria, &c., assumed in practice. though devoid of nectar and visited solely for pollen, The course adopted in this book is to set out as " are not regarded as pollen-flowers but as well clearly as possible what may be called the practical marked bee-flowers.” Even here he is not consistent, theory of the motors, and to follow this up by applicasince Cassia chamaecrista and Solanum rostratum tions of the theory to the design of actual examples. are described as pollen flowers, though they too are This is no doubt the right course, for however valuadapted for bees.

able a knowledge of the fundamental theory may be, H. Müller's important work on the specialisation there are many points of equal importance which can of insects in relation to flowers is fully given, and only be brought out in the calculation of an actual this is a subject often neglected for the converse

motor. instances of floral adaptations. Here

too is

The setting out of the theory of single-phase cominteresting account of differences in habits according mutator

has been made very clear, and as the visitors are of the social or solitary bees. The although circle diagrams are referred to, the author social class, having to work hard for a living, is states very truly that they are of little practical value, forced to visit flowers which the luxurious solitary and that it is better to calculate the current for a few bee neglects. Near the end of the book is a good points from first principles. Particular attention has account of the statistical method of treating the visits been paid to the question of sparking, and its dependof insects, as illustrated chiefly from MacLeod's re- ence on the “transformer voltage," the “reactance searches. The volume concludes with valuable voltage,” and the “rotation voltage " in the coils bibliography comprising 3748 entries, and occupying short-circuited by the brushes. The effect the trans160 pages.

former voltage has on the general design is also clearly The translator has done his work well on the explained, but hardly sufficient reference is made to whole. We must, however, direct attention to a few the magnetising action of the circulating current proinstances of faulty rendering. Thus “ Blumenblätter " duced. is translated by • floral leaves," “ Saft" (nectar) by Turning now to the calculation of typical motors, a “sap." But the few slips in translation that occur series motor of 60 h.p. is worked out, and also a reare not serious; we have no objection to H. Müller pulsion motor of 48 h.p. It is unfortunate that pracbeing described as a genial ” author (p. 25), or tically no indication is given as to how these motors to the incorrect statement that Darwin inherited his rated. At present, single-phase commutatus house at Down (p. Sn), except that they are due to motors are inevitably associated with traction work, in the translator, not to the author.

which it is customary to speak of the one-hour rating But these are trifles in comparison to the fact that | Supposing this to be the intention of the author it his English is thoroughly readable, and this is a must be confessed that the size of the motors is rather standard by no means easy of attainment in trans- large for their output, chiefly on account of the lu** lating from German.

speed chosen. Another objection, which is perhaps

F. D. more serious, is that the windings have been made

an

motors

a

are

or

suitable for very low voltages in the armatures. For Gravenoire skeleton (found in 1891) is doubtful, as it instance, the input of the 60 h.p. motor is about 620 is from one two other places,' while that from amperes at 100 volts. This choice of voltage no doubt Pranal, Blanzat, St. Saturnin, and Neschers is negagreatly facilitates the design from the point of view tive. There is none anywhere to show that eruptions of a low transformer voltage, but such a choice would were contemporary with Neolithic man; but an be almost impossible for traction work, owing to size awakening, as Vesuvius once proved, is possible after of the controlling gear. At this voltage the current a long slumber. Has this been the case in Auvergne? required by four 100 h.p. motors in parallel would be For that, according to some authorities, we have approximately 4000 amperes; and even, if connected historical evidence. Here Prof. Boule's title and pretwo series two parallel, the control of 2000 amperes face led us to hope for some additional information, would involve very heavy cables and switches.

but we have been disappointed. In fact, his disIf, on the other hand, a higher voltage had been cussion of the evidence is hardly so full as that which chosen, a higher value of the transformer voltage it received in the Geological Magazine so long ago would have resulted; but this is precisely the difficulty as 1865. As was then stated, several earthquakes which has to be met in practice. For railway work, occurred about the year 451 A.D., and the wild deer voltages less than 220 are practically unknown.

became so terrified as to take refuge in Vienne. A The book concludes with two appendices, the first third “portent ” happened, but whether this was a of which deals with the theory of the repulsion motor, volcanic eruption depends on the translation of certain taking account of magnetic saturation, and the shift- Latin words in two letters written by bishops. If ing of the brushes; and the second gives some oscillo- these refer to severe fires-possibly the consequences graph tests dealing with the commutation of a small of the earthquakes—the language is extraordinarily motor operating with alternating currents.

bombastic; if to an isolated volcanic outbreak, this Mr. R. F. Looser, in translating this book from the could not be in the “ Puy" district, and there is much German, has accomplished his task with excellent difficulty in locating it nearer Vienne. We do not results.

find that the uncertainty has been diminished by Prof.

Boule's researches; but, notwithstanding this disVOLCANIC HISTORY OF ALTERGNE.

appointment, and though most of the information has

been already published, we welcome as a boon to L'Age des derniers Volcans de la France. Ву

students this clearly written summary of the volcanic Marcellin Boule. La Géographie (Mars, Mai, 1906.) Pp. 64; illustrated. (Paris : Masson et Cie.) history of Auvergne from one who has taken such a

leading part in its elucidation. T. G. BONNEY. 'HE volcanic outbursts of Auvergne are to a certain

extent disconnected locally and different in age. The western group is the more linear in arrangement,

OUR BOOK SHELF. the eastern the more sporadic. In the one, the broad

The Bir of the British Islands. In twenty parts. mass of the Cantal sends off a short spur-Aubrac

By Charles Stonham, C.M.G. With illustrations

by L. M. Medland. Part i. Pp. 40 and plates. to the south-east, and a long one to the north, which

(London : E. Grant Richards, 1906.) Price 7s. 6d. extends through the famous Mont Dore district and terminates in the chain of Puys west of Clermont. To use the language of sport, Mr. Stonham

may Ferrand; in the other group we have the noted chain claim to have established a new record. He has of the Velay and the outlier of Mezenc, Megal, and aimed at a colourless book, and colourless it is, both Coirons. The eruptions, apparently, were the latest to in the plates and in the text, though whether it is begin in the first of these districts, and the latest to

“ far in advance of anything of the kind which has cease in the region of the northern Puys. The tuffs judgment of the reader.

so far been attempted " must be left to the individual and other sedimentary deposits, which are associated In saying this, however, we are far from implywith the lava flows and masses of coarser scoria, have ing, or wishing to imply, that the work is without furnished palæontological data which fix the age of merit; it gives a careful and pleasing description of some of the volcanic outbursts, and make it possible the species and their habits, and shows considerable by a comparative study of the ejecta to synchronise acquaintance on the author's part with most of them;

but nothing strikes us as impressive, nothing as an the discharges in different districts. The materials

addition to our knowledge, nothing, in short, as Oscillate from basalts to andesites, with fairly unlike what may be found without much trouble elseabundant phonolites in two areas, and occasional | where. rhyolites and trachytes among some of the older All this may, of course, be altered when families rocks. The earliest outbursts occurred in the Upper other than the Turdidæ come under discussion, but in

this part—and it is this part that we are called upon Miocene. Volcanic activity ceased in one of the

to notice-we can no sufficient reason for the southern extremities with the Lower Pliocene, in publication of the work. Nevertheless, we infinitely another with the Middle, in the Cantal itself with the prefer it to many other books treating of British Upper. It was prolonged in four districts well into birds, and hope, for the author's sake, that it may the Quaternary, the date of its cessation being still

meet with more success than we anticipate. We can far from certain.

hardly believe, however, that the considerations of fine In the neighbourhood of Le Puy, eruptions, as the

paper, brilliant ink, and so forth, advanced in the

prospectus, will outweigh those of comparative cost. discovery at Denise showed in 1844, were contempor- 61. 155. is no small price for a publication of this aneous with Palæolithic man. The evidence of the kind with black plates, especially when it is proposed

THE

net.

see

one

a

ito relegate the rare and occasional visitors-often of

LETTERS TO THE EDITOR. the utmost interest-to a future supplement, which will enhance the expense.

(The Editor does not hold himself responsible for opinions To the eye of an artist the plates will doubtless expressed by his correspondents. Neither can he undertake appeal as admirable specimens of

the process

to return, or to correspond with the writers of, rejected employed, but to that of an ornithologist they lack manuscripts intended for this or any other part of NATURE.

the life and vigour which in many cases compensate No notice is taken of anonymous communications.]
for an absence of coloration.
Finally, we quite agree with Mr. Stonham that in

Biometry and Biology: A Rejoinder. many species the female and young are well worth

I SHOULD like to preface my remarks on Mr. Lister's depicting, and that it is quite useless to attempt to

reply by relieving his mind from any anxiety about Dr. represent the songs of most birds by a set of syllables Pearl's feelings. °Dr. Pearl is in America, and I cannot, which each reader would in all probabilitymouth

of course,

communicate with him, but I know him differently.

intimately, and am convinced that he is far too good The Manufacture of Concrete Blocks, and their l'se a man of science to feel aggrieved by any criticism of his in Building Construction. Bv H. H. Rice and

writings. He might well feel aggrieved that Mr. Lister W. M. Torrance. Pp. 122. (London : Archibald

supposes him desirous that his paper should remain un

criticised, because the criticism should affect his reput.Constable and Co., Ltd., 1906.) Price 8s. net. tion. I am inclined to think that, as a fellow biometrician, This work is a reprint in full of the two prize papers he will rejoice with me that Mr. Lister's vague charge on concrete block construction in connection with a made at a singularly unfitting moment-has been brought competition instituted by the Engineering News and to a definite issue, and can be tried coram judice. the Cement Age, and, in addition, abstracts are given Had a first-year biometrical student in my laboratori of the papers of ten other competitors, which contain sought advice from a biological freshman about the nature data not given in the prize papers.

of Paramaecium caudatum, I should have anticipated that Mr. Rice in his paper deals fully with the raw he would receive much the information with which Mr. materials--cement, sand and gravel, or crushed stone;

Lister provides us. His remarks could only be made bu

who (a) had either not studied the memoir hwith the mixing and manufacture of the blocks; and with the important questions of curing and facing the criticises, or had failed to perceive the significance of the

constants calculated by the author, and (b) had never blocks with a finer quality of the material, and he attempted accurate measurements on infusoria, or previously briefly discusses the principles underlying the use of

to such attempt been trained to that caution and accuracy this material in building construction.

in measurement which it is the function of biometry 10 Mr. Torrance deals more fully with the form of inculcate. the blocks, illustrations being given of many of the I challenged Mr. Lister to substantiate the charge he moulds for which patents have been granted, and made in August, when, presumably, the grounds of his with the relative cost of buildings of concrete and

insinuation at York were fresh in his mind. He then other material; finally, he states that from an artistic considered that Dr. Pearl's position was traversed by the standpoint the best success so far obtained has been objection that the conjugants individually are possibly or where the process of casting in sand has been adopted, probably differentiated gametes.

What and several reproductions of photographs are given exactly by quotations from Huxley and Romanes :

the author's position? He expresses it to illustrate this point.

“In my earliest criticisms of the Origin' I venturid The abstracts of the other ten papers give much

to point out that its logical foundation was insecure a useful information on many points of detail not dealt long as experiments in selective breeding had not produced with by the authors of the two prize papers, with re- varieties which were more or less infertile, and that in. gard both to the manufacture of the blocks and also security remains up to the present time " (Huxley. “ Lie to their employment in building construction.

and Letters of Darwin," vol. i., p. 170). In an appendix are the rules and regulations govern- “To state the case in the most general terms we m.is ing the use of this material and the testing of the say that if the two basal principles are given in heredits blocks in Philadelphia. There has been quite a flood

and variability, the whole theory of organic prolution

becomes neither more nor less than a theory of homogam: of literature during the past year on reinforced con

--that is a theory of the causes which lead to discriminatı crete, but until this book appeared little had been written in reference to the use of concrete by itself isolation, or the breeding of like with like to the exclusion

of unlike" (Romanes, Physiological Selection ''). for building purposes.

This problem of the divergence of individuals into varisElementary Electrical Calculations. By W. H. N. ties is the one selected by Dr. Pearl, and according tra

James and D. L. Sands. Pp. 216. (London : Mr. Lister is the best example by which he can illustratr Longmans, Green and Co., 1905.) Price 35. 6d.

his statement that biometricians do not select a sound

biological problem “ before bringing a formidable mathnet. This book is based upon a series of lectures given by matical apparatus into action for its investigation." The

is the “hare cooked before it was caught," to cite aga'a the authors to first- and second-year students of elec

Mr. Lister's phrase. Dr. Pearl shows that such homogame trical engineering, and can be confidently recom- exists in an extraordinarily high degree in Paramaettum mended to those for whom it is written. So far as

caudatum. In other words, he has broken entirely notel it goes, it is well arranged and perfectly clear; the ground, which, to say the least of it, renders Hurles's only criticism that can be suggested is that it does position no longer tenable. This is now admitted. alhp? not go far enough. The range of a subject which in a niggardly fashion, by Mr. Lister himself. In Augus? should be studied by first- and second-year students he considered that Dr. Pearl's position was traversed for is, however, a matter for individual teachers to settle. his omission to consider the differentiation of gametes

It will suffice, therefore, to state that the book which was possible or probable. He does not now aven begins with an account of the fundamental units, endeavour to show that it is traversed by this, but sata proceeds to discuss Ohm's law very fully, and devotes that I have claimed for Dr. Pearl the first demonstratin brief chapters to power and work, conversion of of the existence of this differentiation. In others words

he now admits that Dr. Pearl has fulls considered the energy, transmission and distribution treated quite problem of differentiation. In fact, more than half De simply. electrochemistry and photometry. Each

Pearl's memoir is devoted to it. He further twits Dr chapter contains numerous examples fully worked Pearl and myself with not distinguishing between a man out, and a large number of exercises for the student. and his gamete !

was

a

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