June ib, 1910J 



NATURE 



471 



the usual clouds, and only on one night was the sky 

 obscured. Further, he gives a detailed account of his 

 observations of the sky on the night of May 18-19, ^^'^ 

 beyond an exceptionally fine display of the zodiacal light 

 no special phenomena were remarked. 



Photographs of the comet taken at Helwan, Kodaikanal, 

 Johannesburg, &c., were shown at the meeting of the 

 Royal Astronomical Societ}- on Friday last, and all of them 

 show plainly what a striking object the comet was in more 

 favourable latitudes and in clearer skies. The long 

 straight tail is seen to have a \&x\ complicated structure of 

 fine filaments and waves. 



Several observeis have forwarded to us accounts of 

 recent observations of the comet. Mr. Leach, of Malta 

 University, states, on June 8, that the comet had been seen 

 every evening since May 20, and, although fainter, the 

 tail still extended some 20° or 30°. It was best seen on 

 June I, when the tail extended nearly to Jupiter. He 

 also remarks on the change in the appearance of the 

 nucleus, which, latterly, was quite stellar in character 

 and of about the second magnitude. 



Mr. J. \V. Scholes, of Grimscar, Huddersfield, sends an 

 account of observations made at Morecambe Bay. A 

 sketch, made at 11. 10 p.m. on May 31, in a clear, cloud- 

 less sky, shows three plumes, or tails, two shorter ones 

 lying beneath, and separate from, the main tail. The 

 lowest, and shortest, is quite near to Castor and Pollux, 

 and nearly parallel to a line joining them. No simple, 

 definite explanation of this apparition is yet forthcoming. 



PAPERS ON INVERTEBRATES. 

 TN the May number of the Entomologist's Monthly Maga- 

 zine. Dr. D. Sharp records the history of the dis- 

 covery in the New Forest of a new species of arboreal 

 beetle of the genus Corticaria. One species of this genus, 

 C. similata, was for thirty-seven years known as British 

 only by a single specimen. In 1908' beetles of this genus 

 were taken on an oak-tree in the New Forest and identi- 

 fied with that species, which they seemed to indicate to be 

 sexually dimorphic. Other specimens procured, both in 

 the Forest and at Woking, demonstrated, however, that 

 not only was C. similata re-discovered in Britain, but that 

 the former area is the home of a new species, for which 

 the name C. lambiana is proposed. C. similata has been 

 subsequently taken in Scotland. 



To the Proceedings of the Academy of Philadelphia for 

 December, 1909, Mr. T. H. Montgomery contributes the 

 second part of his observations on the habits of spiders. 

 Particular interest attaches to his account of the breeding 

 habits of Pisaurina, the species of which closely resemble 

 the Lycosidae in structure, but differ by being arboreal 

 instead of terrestrial during the cocooning season, and in 

 carrjing the cocoons by means of the chelicera instead of 

 suspended from the spinnerets. The large white cocoons 

 of one species are usually found on poison-ivy (Rhus 

 toxicodendron) ; and from observations on specimens kept 

 in confinement it appears that the female carries the 

 cocoon about with her until a few days before the voung 

 are ready to hatch. As they emerge, she commences to 

 enclose them with a network of lines, she herself remaining 

 on the outside of the nest thus formed. In this manner the 

 old cocoon and the young spiders are eventually enclosed 

 in a complete nest, which may take as much as three days 

 to construct. 



The January and February issues of the same serial for 

 the current year are occupied by papers on molluscs — for 

 the most part American land and fresh-water forms— among 

 which the longest is one by Messrs. Pilsbry and Ferriss, on 

 the land-snails of the south-western States. As the result 

 of their study of Arizona snails, the authors have been 

 led to doubt the power of environment as a main factor in 

 the differentiation of species, and to regard this as capable of 

 explanation only on the hypothesis of variations in the egg, 

 leading to modifications of the organism, for the most part 

 not affecting the well-being of the race. Such adaptation 

 as exists is probably due to selection, and the isolation of 

 colonies would favour the perpetuation of mutations. 



Fresh-water gastropods of the genera Limnea and Physa 

 progress, it is well known, by crawling, back-downwards, 

 on the surface-film of the water. On p. 42 of the serial 



NO. 2120, VOL. 83] 



just cited Mr. H. S. Cotton shows that the same mode of 

 progression occurs in the case of a marine bivalve of the 

 genus Modiolaria, the remarkable feature in this instance 

 being the small size of the area of adherence. 



To the May number of the American Naturalist Dr. 

 H. A. Pilsbry communicates a note on a new t>pe of 

 barnacle {Stomatolepas praegustator) inhabiting the mucous 

 membrane of the throat of the loggerhead turtle. Although 

 sessile barnacles are well known to infest the external 

 surface of turtles and whales, while certain parasitic forms 

 penetrate the integument of their crustacean hosts, no 

 commensural thoracic tv'pe appears to have been previously 

 described. Stomatolepas belongs to the subfamily Coro- 

 nulinae, and is nearly related to Tubicinella, which lives 

 on the skin of whales, and Stephanolepas, a barnacle found 

 imbedded in the horny plates of the shell of the hawksbill 

 turtle. 



SOME BIOLOGICAL SERIALS. 

 'T'HE frequency with which the successive numbers of 

 -^ the Quarterly Journal of Microscopical Science make 

 their appearance may be taken as an index of the activity 

 in research — of a particular kind — on the part of British 

 biologists, and the editor is to be congratulated on the 

 issue of seven parts of what used to be literally a quarterly 

 journal during the last twelve months. The April number 

 (vol. Iv., part i.) maintains the usual high standard of this 

 publication. It opens with a detailed description, by Prof. 

 G. C. Bourne, of the anatomy of a remarkable New 

 Zealand mollusc, Incisura (Scissurella) lytteltonensis, illus- 

 trated by five carefully drawn plates. Mr. W. J. Dakin 

 gives a very full description and discussion of the eye of 

 the scallop — Pecten — an organ which, on account of a 

 certain resemblance to the vertebrate type of eye, has for 

 a long time past attracted a large share of attention from 

 biologists, and which lately, we believe, has played a not 

 unimportant part in the theories of philosophers. Mr. 

 Dakin concludes that " there is no ground whatever for 

 placing the Pecten eye in the same class as the vertebrate 

 eye, for the resemblance is very superficial, and though 

 the retina is inverted in both cases, this has been produced 

 in very different wajs." Prof. E. A. Minchin and Dr. 

 H. M. Woodcock have a paper on the blood-parasites of 

 certain fishes, accompanied by three of those remarkably 

 beautiful plates which we have learnt to expect from proto- 

 zoologists. A special welcome should be extended to 

 another protozoological paper, the first, we believe, from 

 the pen of Mr. Julian S. Huxley, grandson of Prof. T. H. 

 Huxley, which deals in a verj- thorough manner with a 

 new genus and species of gregarine from the digestive 

 tract of that remarkable crustacean Anaspides tasmaniae. 

 Both this memoir and that by Prof. Bourne, already re- 

 ferred to, are based on material obtained by Mr. Geoffrey 

 Smith on his recent trip to Australasia. The number con- 

 cludes with a reprint of Prof. Hubrecht's address to the 

 Boston meeting of the International Zoological Congress 

 on the fcctal membranes of the vertebrates, in which the 

 author elaborates his remarkable views on the interpreta- 

 tion of mammalian development. 



In the second volume of the Zeitschrift fUr induktive 

 Abstammungs- und Vererbungslehre Prof. G. Steinmann 

 further elaborates his theory of the extreme polygenetic 

 origin of the Mammalia. This is a new and somewhat 

 startling hyppAesis which does not seem, as yet, to have 

 attracted much attention in this countrv- ; its acceptance 

 would involve a far-reaching modification of generally 

 adopted views as to the phylogeny of the Vertebrata. The 

 reptiles, which are themselves supposed by Prof. Steinmann 

 to have arisen polyphyletically from the Amphibia, are 

 divided into two groups, the Orthoreptilia, which include 

 the existing crocodiles, chelonians, lizards, and snakes, and 

 the Metareptilia, which include extinct forms which have 

 no reptilian representatives at the present day. The Meta- 

 reptilia are again divided into Avireptilia, which are sup- 

 posed to be the ancestors of the birds, and Mammoreptilia, 

 from different groups of which the various lines of 

 mammalian descent are traced. Thus the Ichthyosauria 

 are regarded as the ancestors of the Delphinoidea, the 

 Plesiosauria of the Physeteroidea, the Thalattosauria of 

 the Mvstacocoeti, the Pterosauria of the Chiropter'* tne 



