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Is it possible to state the gist of the contribution which the almost too analytic author has to make? Like draws to like; animals with similar acquired characters tend to come together and keep together in habitudinal segregation; "isolation" and "selection" in their varied forms work on inborn variations, and the habitudinal segregation is replaced by a stabler racial segregation. Segregate breeding, fortified by physiological and psychological incompatibilities, results in divergent evolution. "The whole process of bionomic evolution, whether progressive or retrogressive, whether increasingly ramified and divergent, or increasingly convergent through amal gamation, is a process by which the limitations of segregate breeding are either set up and established or cast down and obliterated." It is of value that all the various possibilities and actualities of segregation should be analysed out and illustrated as Mr. Gulick has so painstakingly and ingeniously done; and another great merit of the book is the insistence on the fact that, even in the case of invertebrate animals, members of the same species, exposed to the same environment in isolated groups, will often arrive at divergent methods of dealing with the environment, and so subject themselves to divergent forms of selection. Just as the social group may learn to determine its own social evolution, so, Mr. Gulick maintains, justly, we think, that the animal is in some measure master of its fate, and that changes in the organism are not controlled in all their details by changes in the environment. We are too much given to ranking the environment always first and the organism second; Mr. Gulick thinks this is putting the cart before the horse; and in this insistence on active or endonomic selection, he does not stand alone. For, as he says, there has been during the past ten or fifteen years an increasing recognition of the fact that not only sexual selection but other autonomic factors are more or less effective in controlling the forms of selection, and, therefore, in controlling the transformations of organisms. Do we not thus reach one explanation of the continuous advance the determinate evolution-of certain large classes of animals? The recognition of autonomic factors in the process of evolution is giving new insight into the self-developing endowments of the organic world. In conclusion, we must direct special attention to the fact that Mr. Gulick's contribution to our understanding of the

intricate factors of evolution is all the more valuable that he rises from biology to sociology-from the Hawaiian snails to Man himself. J. A. T.

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Société Entomologique de France." These prints comprise a useful résumé of recent papers and discussions at the meetings of the English Entomological Society during the last three years on bionomic subjects, as well as the two presidential addresses of Prof. Poulton to that society on the questions, "What is a Species?" and "Are Acquired Characters Hereditary?" and in this and in other ways they deal with many matters of extreme interest to naturalists generally. These prints are followed by the reports proper, belonging to the great Hope collection, one for each of the years 1903, 1904, and 1905, occupying together nearly 160 pages. They tell a story of expansion, classification, and orderly rearrangement, all on an extensive scale. It is satisfactory to learn that the very considerable work which this entails is making great progress, and that, with the voluntary assistance so liberally given by competent persons in the different departments, the task of overtaking arrears is being rapidly pursued. The time seems not far distant when, notwithstanding the labour involved in disposing of the immense numbers of new specimens flowing in from various sources, there will be little wanting and much to approve in the Hope Museum as a reference and self-explanatory collection. Very valuable service has already been rendered by it and its officers and staff as a consulting and educative authority for effective observation by entomologists proceeding abroad.

Incidentally, many interesting observations find a place in the reports bearing on matters which have recently engaged much attention; among these reference may be made to illustrations of the extent to which insects are attacked by vertebrate animals, as well as by those predaceous two-winged flies, the Asilids, which successfully attack the stinging Hymenoptera, as well as less formidable victims often much larger than themselves.

A large part of the report for 1903 is devoted to an account of the work done upon the immense Burchell collection presented in 1866 to the Hope Museum by the sister of the illustrious naturalist, including the preparation of a complete and efficient catalogue. In connection with this the interesting story is told of the discovery, as the result of a lecture given by Prof. Poulton at Cape Town, of a portion of Burchell's original journal written in his ox waggon.

Hope

South Africa has been in so many ways disappointing that it is pleasant to find evidence in the Reports" of its extraordinary value to zoological science. Prof. Ray Lankester, in his recent address as president of the British Association at York, has told us that the study of insects, especially of butterflies, is one of the most prolific fields in which new facts can be gathered in support of Darwin and new views tested. It is not, therefore, surprising that many pages of the reports are devoted to butterflies, and to the numerous examples they furnish as to the magnitude and extraordinary character of the different kinds of variation they present, especially those from South Africa, differences in size, form, colour, and habits between parents and offspring and between offspring

inter se, and the association of some of these differences with differing seasons and climates. Many large additions exhibiting striking variations of these kinds are recorded in the descriptions given of collections of butterflies received from South Africa, so wonderfully rich in these varied forms, as well as from New Zealand, the islands of the Indian Ocean, and elsewhere.

Special arrangements made at the museum for the study and illustration of mimicry in various orders of insects are described. All the orders receive attention and study there, and with such an affluence of contributors from all parts of the world, with the aid of the numerous willing and capable helpers to whom Prof. Poulton heartily acknowledges the obligations that science owes them, and with the enthusiastic and intelligent interest in the subjects that manifestly prevails in every department of the institution, the Hope Museum is plainly pursuing a career that is rendering it of great and increasing scientific value. F. M.

OUR BOOK SHELF.

Insect Pests of the Farm and Garden. By F. Martin-
Duncan. Pp. vii + 143;
illustrated. (London:
Swan Sonnenschein and Co., Ltd.) Price 2s. 6d.

net.

THIS little book appears in the Naturalists' Library Series. It deals with a number of common insects that are destructive in the field and garden, and at least one rare one. The printing and illustrations are good on the whole, and it is clearly and interestingly written. There are, of course, printer's errors, such as Brachus for Bruchus, Centorhynchus for Ceutorhynchus, ovae for ova, &c. A few illustrations are scarcely recognisable, such as that of the codling moth (Fig. 38), the currant gall mite, and the gooseberry red spider (the currant mite, evidently copied from the Board of Agriculture leaflet, being particularly poor, and quite unlike the actual acarus).

No

When one reads the part dealing with treatment the impression is at once formed that the author is not only not practically acquainted with the subject, but is not au fait with any up-to-date work. mention is made of the most important insecticides, &c., such as arsenate of lead, which is superseding Paris green, caustic alkali wash, bisulphide of carbon, &c., whilst many of the receipts given are quite out of date.

Such advice as picking up maggotty apples, the cleaning of hop poles, and burning the bine, &c., will scarcely meet with the approval of farmers, and is certainly not necessary. One does not now see many hop-poles about to clean. Nothing up to date is given concerning wireworm, whilst, on the other hand, people are cautioned against having animals and fowls in orchards sprayed with Paris green; the author evidently knows nothing of the experiments carried out which show that we can safely keep stock of all kinds in the orchards even when they are actually being sprayed.

Some of the scientific names used are wrong; that of the celery fly is not Tephritis onopordinis; the names of the diamond-back moth and the red spider of hops are also wrong.

The work has evidently not been compiled from sufficiently up-to-date material to recommend it to the notice of practical men, and there is nothing new in it of scientific value.

Elementary Electrical Engineering in Theory and Practice. By J. H. Alexander. Pp. xii+208 (London: Crosby Lockwood and Son, 1906.) It is difficult to find much in this book to recommend It is evidently not intended for the higher classes of students or engineers, but this fact is scarcely sufficient to warrant an entire absence of logical sequence or method in the arrangement of the material. The scope of the book is far too wide, taking in as it does fundamental principles, measuring instruments, electrical machinery, batteries, cables, transmission, and generating stations.

Such a wide range compressed into two hundred pages must inevitably lead to a superficial grasp of the subject. For instance, what can be the utility of such a paragraph as the following?

"Storage cells are always fixed up in a separate room. Brickwork or stone, laid in cement and concrete, are used for the foundations for the machinery The coal bunkers should allow of a store of coal supply for three or four weeks."

The author would be well advised to concentrate his attention on one of the sections mentioned abou instead of attempting to include in a single volume so much that cannot adequately be treated in so small a space.

Immanuel Kants Grundlegung zur Metaphysik der Sitten. Dritte Auflage. Edited by Karl Vorlander. Pp. xxx + 102. (Leipzig: Verlag der Durr'schen Buchhandlung, 1906.) Price 1.40 marks.

THIS is the third edition of one of Kant's best-known works in the excellent series of the Philosophische Bibliothek. The introduction contains a well-informed account of Kant's occupation with ethical subjects between the years 1764 and 1785, and of the interest excited by the publication of the "Grundlegung." The text is based on the best authorities, and variant readings are added in the footnotes. A full index names and subjects completes the volume.

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The letter begins :-"I should fancy from the review by G. H. B.' in NATURE of July 10 (p. 265) that the papers of Prof. Levi-Civita relate largely to the med transformation of Lagrange's equations, the complete theory (Proc. Camb. Phil. Soc., vol. vi., p. 117; Hydrodynamics, vol. i., p. 171) of which was first given by myself so far back as 1887 "; it is then shown that the mixed form of Lagrange's equations may be obtained in the most simple way through an elegant artifice of elimination.

The words here quoted give the impression that my papers deal principally with the announced theory, and that they may be little more than the reproduction of readers of NATURE to know-and Mr. Basset will be the some previous papers by Mr. Basset. I wish, however, the first to recognise the fact that the case is quite different. The papers in question (as it appears from the general title, Sur la Recherche de Solutions particulières des Systèmes différentiels et sur les Mouvements stationnaires," and as it seems to me to result also from the review by

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I Do not recollect by whom the phrases "ignoration of coordinates" and "ignored coordinates were originally introduced, but on consideration I am of opinion that they are singularly inappropriate ones, and I much prefer the phrase kinosthenic coordinates."

The advantages of the mixed transformation are that, whenever a generalised momentum is known to be constant the motion can be determined without knowing anything about the coordinate or the velocity corresponding to this momentum. The first trace I can find of this idea is contained in a paper published by Lord Kelvin about 1872 (see Hydrodynamics," vol. i., p. 177).

The discovery of the mixed transformation was the result of certain hydrodynamical investigations relating to cyclic irrotational motion, but the circumstance that I originally published it in a hydrodynamical form may have obscured the character of the result as a general theorem of dynamics. A. B. BASSET.

September 4.

The alleged Triassic Fcraminifera of Chellaston, near Derby.

IN NATURE for July 26, in a notice of Mr. FoxStrangway's memoir on the Loughborough district, reference is made to certain Foraminifera of Liassic type, at one time believed to come from the local Trias. Prof. Rupert Jones, F.R.S., has kindly directed my attention to his explanation of the matter in the "Foraminifera of the Crag, part ii., p. 161, published by the Palæontographical Society in 1895. He there gives a history of the observations, including personal inquiries, and believes that the Foraminifera in question came from Liassic clay in Leicestershire, which was "inadvertently thrown in with the red clay' on its journey to Cubitt's works in London.' Mr. Fox-Strangways gives a reference to this passage, but does not quote it, and suggests on his own part that the Foraminifera may have come from Liassic material in the drift. GRENVILLE A. J. COLE.

White- and Brown-shelled Eggs.

BIRDS which lay their eggs in comparatively unprotected places and in a hollow in the ground, as is the case with the pheasant, partridge, jungle fowl, &c., always lay coloured eggs closely resembling in tint the colouring of their surroundings. White-shelled eggs are laid only by birds which make a good nest-those which make it in a secluded spot, or which take the precaution of covering their eggs with leaves, &c., when they are off the nest. It is a strange fact, therefore, that the non-sitting breeds of our domestic fowls lay white-shelled eggs, whereas in the eggs of the sitting or Asiatic breeds the protective colouring is retained in the shell of the egg. This loss of colour cannot be merely the result of centuries of domestication, or all breeds of domestic fowls would lay white-shelled eggs. The systematic repression of the maternal instincts of the hen carried on by man for a number of years has certainly produced the white-shelled egg. It would almost appear to be the case that the hen, knowing she will have nothing to do with the hatching and rearing of the chicken in the egg, loses all interest in the egg, and leaves it, as it were, to its fate. For this reason she neglects in some mysterious way to impart to the shell the protective colouring which is so necessary, in a state of nature, for the preservation of her race. If this be really the case there is an insurmountable obstacle in the way of obtaining brown eggs from the non-sitting breeds of domestic hens, and poultry keepers are only wasting time in trying to accomplish the impossible. L. M. F.

FLASHLIGHT PHOTOGRAPHS OF WILD ANIMALS.

FR

ROM the popularity of his well-known work "Mit Blitzlicht und Büchse " (or its English translation, "With Flashlight and Rifle "), there is, we believe, a very general impression that Mr. C. G. Schillings was the pioneer in the practice of photographing big game animals by night in their native haunts by combining the use of the flashlight with the camera. It appears, however, from a most interesting and profusely illustrated article in the July number of the National Geographic Magazine that the true claimant to this position is an American

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sportsman, the Hon. George Shiras. With regard to his position in the matter of flashlight-photography, Mr. Shiras writes as follows:

"While a number of the present illustrations were taken in the daytime, this method of photography is now so well known that I will not attempt to describe such pictures in detail; but in view of the fact that I was the first to attempt flashlight pictures of wild game, and for the first fifteen years was the sole occupant of this attractive field of photography, it may be of interest to the readers of this article to learn something about this rather odd way of picturing wild animals."

One of the author's most successful plans in the forests of North America was to mount his apparatus in the bow of a boat manned by a selected crew, and then to set forth in search of his quarry. Describing the photographing of a deer the presence of which has been made known by the light reflected by his eyes, the author writes that "The flashlight-apparatus has been raised well above any obstructions in the front of the boat, the powder lies in the pan ready to ignite at the pull of a trigger; everything is in readiness for immediate action. Closer comes the boat, and still the blue translucent eyes watch it. . . .

its own portrait, and here again we may quote the author's own phraseology :

"A string is passed across a runway or other poin where the deer are likely to pass, which, when touched, sets off the trigger and ignites the mag nesium powder. The same method can be used for daylight pictures, except that here a slender black thread is laid across the path, one end of which is attached to the shutter of the camera. The shutter revolves as soon as there is any pressure upon the thread, and a picture of any passing object is taken instantaneously. Not the least interesting part of this species of photography is that the operator does not know until he develops his plates what manner of beast, bird, or reptile has caused the shutter to open.

Although many of the portraits thus obtained are not in every de tail satisfactory to the naturalist, yet they frequently reveal the animal in characteristic and unsuspected attitudes, or display peculiar alarm-features, such as the expansion of the hairs of the light rump-patch of the wapiti revealed in one of the author's pictures. Such pictures are indeed especially valuable in the case of many of the smaller mammals, the nocturnal habits of which make it so difficult to become acquainted with their mode of life.

Whether photography-flashlight or otherwise-will, as the author and Sir Harry Johnston (in the introduction to the English edition of Mr. Schillings's book) hope. ever induce sportsmen to be satisfied with pictures instead of the lives of their quarry remains to be

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seen.

R. L.

FIG. 2.-A Raccoon taking his own portrait. From the National Geographic Magazine.

Suddenly there is a click, and a white wave of light breaks out from the bow of the boat-deer, hills, trees, everything stands out for a moment in the white glare of noonday. A dull report, and then a veil of inky darkness descends. Just a twenty-fifth of a second has elapsed, but it has been long enough to trace the picture of the deer on the plates of the cameras, and long enough to blind for the moment the eyes of both deer and men. Some place out in the darkness the deer makes a mighty leap; . . . and soon he is heard running, as only a frightened deer

can.'

A variation of the plan is to let the creature take

A SEARCH FOR A BURIED
METEORITE.

THE mode of origin of a re

markable terrestrial feature, known as Coon Butte or Coon Mountain, has been the subject of much speculation and study, of which an account was given in the year 1895 to the Geological Society of Washington by Mr. Grove Karl Gilbert, of the United States Geological Survey, in a presidential address entitled "The Origin of Hypotheses."

This so-called mountain, situated in Central Arizona, rises only 130 to 160 feet above the surrounding plain. When climbed, it is found to contain a crater 530 to 560 feet deep, the dry bottom being thus 400 feet below the level of the land surrounding the rim The crater is almost exactly circular, and is nearly three-quarters of a mile across, two diameters at right-angles with each other measuring 3654 and 3808 feet respectively. From the crest of the rim to a distance of about three and a half miles outwards the surface of the country is strewn with fragments of sandstone of various colours; for the first half-mile the fragments are large blocks, som of them of enormous size, 60 or even 100 feet in

diameter; for the next half-mile the fragments are smaller and less plentiful; beyond this distance they are isolated from each other, and become smaller and Iss frequent as the distance from the crater increases. In 1886 some shepherds encamped on the slopes of Coon Mountain found among the rock-fragments on the rim some lumps of iron, which they mistook, As is not infrequently the case, for native silver. The general distribution of the fragments and the nature of their material suggested to the shepherds that all the scattered masses, both stony and metallic, had been shot from the crater of the mountain. A ew years later some of the metal fell into the hands of the late Dr. A. E. Foote, of Philadelphia, for whom it was analysed by Prof. G. A. Koenig, of that city. In Structure and chemical composition the metal proved to be identical with ordinary meteoric iron, but of xceptional interest as enclosing microscopic diamonds. Since that time the celestial origin of the iron masses found about Coon Mountain has been recognised as beyond doubt, and the meteorite has become well known under the name of Cañon Diablo, small masses having been found in the cañon of that name distant about two and a half miles from the mountain. During the oral discussion which followed the reading of the paper of Dr. Foote on August 20, 1891, before the American Association for the Advancement of Science, Mr. Gilbert, who chanced to be present, suggested that the fall of the iron masses might have been connected with the formation of the crater, and that the large hole might have been caused by the penetration of the earth by an enormous iron meteorite, perhaps 1500 feet in diameter, large enough to be termed an asteroid. In such case the asteroid is buried in or near the hole and probably at no great depth.

Not being at that time at liberty to visit Coon Mountain himself, Mr. Gilbert asked his colleague, Mr. Willard D. Johnson, to examine the district and try to discover what had been the mode of origin of the crater. On his return Mr. Johnson reported that the crater had probably been produced by a tremendous steam explosion, the fragmental material around being the original contents of the hole. Within a radius of fifty miles there are hundreds of vents, from which lava has issued during the later geological periods, and thus there existed at one time a neighbouring mass of molten material sufficient to account for the production of the required amount of steam. In such case the fall of the masses of iron had been independent of the formation of the crater.

The rocks in the region containing the crater, however, are stratified and of sedimental origin, and the strata, except at the hole itself, are still quite horizontal. They are of late Carboniferous age, and consist, to a considerable depth, of coloured sandstones, one kind being so calcareous as to have claims to be regarded as a limestone. But all round the hole itself the strata have been bent, and are now directed upwards, approximately towards the same point.

This explanation and report being of an extraordinary character, Mr. Gilbert's interest in the problem became even greater than before, and he soon seized an opportunity of making an examination himself. This was done with such minuteness that he was able to draw contour lines of the crater and district for every ten feet of difference of level, and could form an approximate estimate as to the positions of the contour lines at the time the crater had been formed; hence he was able to calculate the respective volumes of the crater and the fragmental material. He came to the conclusion that the two volumes were virtually equal (eighty-two millions of cubic yards), and thus that no asteroid could have buried itself

there. Further, he made a delicate magnetic survey of the district; no magnetic disturbance being discoverable, he concluded that no mass of iron large enough to have produced the crater could be lying within some miles of the earth's surface, whereupon he renounced the asteroidal hypothesis, and accepted the explanation which had been given by his colleague. Some years later the crater and the speculations as to its origin became known to Mr. D. M. Barringer and Mr. B. C. Tilghman. They formed the opinion that the asteroidal hypothesis had been renounced by Mr. Gilbert on insufficient grounds. In the first place, according to their calculations, there is a great difference between the volume of the crater and that of the fragmental material; in the second place, the absence of magnetic disturbance may be due to the asteroid having been broken up into smaller masses, each of them polarised, and each having its magnetic axis in an accidental direction. So convinced were they that in 1903 they "located " the mountain under the United States Mineral Land Laws, and at great expense proceeded to sink shafts and make bore-holes with the hope of finding the buried asteroid. The results of this work, so far as it has yet gone, were recently recorded in two papers published in the Proceedings of the Academy of Natural Sciences of Philadelphia (December, 1905). One of them has been written from the point of view of the geologist (Mr. Barringer), the other from those of the physicist, chemist, and mathematician (Mr. Tilghman). The former says:-" They do not leave in my mind a scintilla of doubt that this mountain and its crater were produced by the impact of a huge meteorite or small asteroid"; the latter feels that "he is justified, under due reserve as to subsequently developed facts, in announcing that the formation at this locality is due to the impact of a meteor of enormous and unprecedented size."

It may be mentioned that a few years ago a successful search was made by Finnish geologists for a large meteorite which was believed by them to have buried itself within a certain area. But in that case the presumptive evidence was very strong. A meteor had lighted up a large extent of the country, and the next morning a newly made hole, with cracks radiating from it in various directions, had been found in the ice covering the Baltic Sea, near Bjurböle, in Finland. After a patient search the mass was at last located at a considerable depth below the sea-bottom, and eventually extracted. What are the prospects of a similar success at Coon Mountain?

For many miles round the crater the order of succession of the rocks, beginning at the surface, is as follows:

(1) Red sandstone, 20 to 40 feet thick.

(2) Yellowish (calcareous) sandstone, 200 to 350 feet. (3) Whitish sandstone, probably 400 to 500 feet. (4) Yellow sandstone, thin layer.

(5) Reddish-brown sandstone. more than 1000 feet. The uppermost stratum has been largely eroded, and remains only as widely separated flat-topped buttes scattered about the plain.

This upper stratum of red sandstone still existed at the place at the time when the crater was formed, for it is the material of the upper part of the rim. It has been raised 140-180 feet above its original position. The upper part of the interior of the crater consists of sandstone cliffs, the lower part of talus. The lower portion of the latter is covered with horizontally stratified sediments having a total thickness of 60-100 feet and a nearly level upper surface of circular outline and 1800 feet in diameter. The material must have settled in a shallow fresh-water lake once occupying the crater.

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