i6 



KNOWLEDGE .^ SCIENTIFIC NEWS. 



[Feb., 1904. 



from the dentition, is to be found in the smaller bony 

 roof of the mouth, and the narrower \omers. Another 

 skull, which is made the type of a new genus and species, 

 under the name of Stowmctopon iaylori, comes still nearer 

 to the tuatera. Other specimens show that the reptile 

 previously described as Oniithositchus is not, as originally 

 supposed, a dinosaur, but is more nearly related to Phyto- 

 saiinis {Belodon), which latter Mr. Boulenger, like the 

 author of the under-mentioned memoir, thinks should be 

 removed from the Crocodilia to an order apart. 

 * * * 



Classification of Reptiles. 



An extremely important memoir on the classification 

 of reptiles is published by Professor H. F. Osborn, in the 

 Memoirs of the American Museum. Following the lead 

 of certain other writers, the author proposes to divide 

 reptiles into two main stems — Synapsida and Diapsida ; 

 the former including the primitive Cotylosauria, the 

 mammal-like Anomodontia (exclusive of the American 

 Pelycosauria), Chelonia (tortoises and turtles), and 

 Sauropterygia (plesiosaurs), and the latter all the other 

 groups. The one branch, it is urged, gave rise to 

 mammals, and the other to birds. The main line of 

 cleavage between the two branches is the single, or 

 undivided, temporal arch (and the consequent presence 

 of only one temporal vacuity) in the former, and the 

 duplication of the same arch in the latter. 



The divergence from the classification usually adopted 

 in this country is not very great, if one factor be borne 

 in mind. European writers usually classify animals 

 according to their degree of evolution, while American 

 naturalists prefer a phylogenetic scheme. That is to 

 say, the former draw their lines of division horizontally, 

 and the latter vertically. A case in point is afforded by 

 the ancestry of the horse, treated in our last issue. 

 American writers would include in the Eqitida all the 

 members of the series down to and inclusive of Hyra- 

 cothcrium, w-hereas English naturalists place in that 

 family only the really horse-like latter forms, while they 

 would refer the earlier types to other families, among 

 which would be embraced the ancestors of the tapirs 

 and certain " non-adaptive " forms. Much may be said 

 in favour of both schemes ; which, instead of being op- 

 posed to one another, are in reality different aspects of 

 the same view. 



Duration of Pregnancy in the Badger. 



It is not a little remarkable that there should still be great 

 doubt in regard to such an apparently simple matter as 

 the duration of pregnancy in the badger. A. writer in 

 the December number of the Zoologist considers that the 

 period is about 12 months, whereas another observer had 

 some time ago put it at about 4^ months. Perhaps the 

 true explanation may be that suggested in Sir H. John- 

 ston's " British Mammals," namely, that the normal 

 period is about six months, but that, as in the roe-deer, 

 under certain circumstances, development may be so 

 retarded as to make the time of gestation double that 

 length. , -<■ * 



Evolution of Marsupials. 



An important memoir by Dr. B. A. Bensley, on the 

 evolution of Australian marsupials, has just been pub- 

 lished in the Transactions of the Linnaan Society. In 

 regard to the origin of marsupials generally, the author 

 is of opinion that the vestigiary placenter of the 

 vansicoots has been independently acquired, and is not 

 therefore indicative of descent from placentals. Never- 

 theless, he admits the comparatively near relationship of 

 placentals and marsupials. The latter are believed to 

 have been primarily differentiated by the assumption of 



arboreal habits, and the earliest forms that can be defi- 

 nitely assigned to the group are the opossums, which 

 thus form the stock of all the modern types, with the 

 possible exception of the Tasmanian wolf, or thylacine. 

 This arboreal radiation distinguishes marsupials from 

 the extinct creodonts, which were terrestrial. At the 

 same time, the thylacine, which it is suggested may have 

 been a foreign immigrant into Australia, appears to bfe 

 related to certain middle tertiary South American types 

 (sparasrodonts), which may themselves be connected with 

 the creodonts. How this fits in with the arboreal 

 ancestry of the other marsupials is left unexplained. 



That curious creature, the gigantic extinct Thylacoles 

 of Australia, originally regarded by Owen as carnivorous, 

 but considered by Flower as herbivorous, is reaffirmed 

 to be a flesh -eater. 



As regards the date when marsupials first reached 

 Australia, there has been much difference of opinion, 

 Wallace giving it as Jurassic, Spencer as Cretaceous, 

 and Lydekker as Eocene ; the author considers that it 

 did not take place till Miocene times. Whether the 

 route traversed was via the !Malay .\rchipelago and 

 Papua, or by Antartica, is left undecided. There are 

 many other points of interest in the memoir, to which 

 lack of space forbids allusion. 



Death of Prof. Karl von Zittel. 



Palaeontologists throughout the world will hear with 

 deep regret of the death of Professor Karl von Zittel, 

 which took place at ^Munich from heart-affection. Pro- 

 fessor Zittel is most widely known by his splendid 

 Manual of Palaontology, of which a smaller edition was 

 published as a Handbook. The latter has been trans- 

 lated into French, and two volumes of an English 

 (somewhat modified and expanded) edition have also 

 appeared. Much original palaeontological work was 

 also accomplished by the late Professor. 



The Electric Eye, 



Curious Experiments with Electric Sparks. 



Mr. Walter J. Turney describes in the Scientific 

 American Supplement some very interesting experiments 

 showing results which he attributes to the ultra-violet 

 rays of light. An ordinary half-inch Ruhmkorff coil has 

 the knobs of its terminals so adjusted that sparking just 

 fails to take place across the gap. On presenting a con- 

 ductor to the inner side of either knob, vigorous sparking 

 at once takes place and continues so long as the conductor 

 remains, ceasing as soon as it is removed. If, however, a 

 non-conductor be presented in the same way, a precise 

 result, oddly enough, ensues. A piece of bare wire, W, 

 about four inches long, was next attached to one of the 

 knobs, and bent round as shown in the figure. If the 

 conductor C be presented to the end, T, of the wire, con- 

 tinuous sparking will occur at the gap G. On now 

 placing a screen, P, of cardboard, glass, or metal, so that 

 G is invisible from T, sparking will cease, but will 

 recommence so soon as the screen is removed. If, how- 

 ever, the screen be of rock-crystal, gypsum, rock-salt, or 

 alum, the sparking will not be interrupted thereby. 

 In another arrangement tried, a mirror was introduced 

 to reflect the image of the junction on to the spark gap, 

 with similar results, as though the spark could see what 

 was going on. 



A further modification was the introduction of a square 



