April io, 1902] 



NA rURE 



549 



and tidal inlets on the aliove-named island. Of 13 species thus 

 obtained, seven were described as new to science and three were 

 regarded as belonging probably to new genera. One of these 

 genera (Kuria), it appeared, could not be referred to any of the 

 recognised families of Amphipoda. 



Zoological Society, March iS.— Dr W. T. Blanford, 

 K.R.S., vice-president, in the chair. — Dr. H. Gadow, F.R.S., 

 read a paper on the evolution of horns and antlers. He stated 

 that three main types could be distinguished in the evolution of 

 the ornamental weapons on the heads of ruminants, and that 

 all these types were referable to an ancient condition in which 

 the beginning weapon, be it one of offence or defence, appeared 

 as a mere exostosis with a thickened skin-pad. This stage 

 resembled that of Dinoceras of the Eocene. Secondly, there 

 was found exostosis of the frontal bone producing a pedicle, 

 surmounted by a cartilaginous mass of apical growth, which by 

 subsequent basal ossification became an antler. Skin originally 

 unaltered and hairy ; this, and the chondrostoma or cartilaginous 

 later osseous growth, was shed periodically and constituted the 

 cervine type. A side issue of type ii. was that of pro-girafife- 

 like animals. Cartilaginous growth preponderant, with multiple 

 and broadened bases. Ossification delayed, but still proceeding 

 from the base, e.g. the Samotherium of the topmost Miocene. 

 A further development of this type (ii. a) was shown by the 

 giraffe, in which the outgrowth proliferated freely and now 

 formed free growths, ossifying independently, of the cranial 

 bones, but ultimately fusing with them. Type iii. was a con- 

 tinuation of the main line from ii., represented by the prong- 

 buck ; predominant epidermal growth produced a horn shoe, 

 which was periodically shed, but had abolished the shedding of 

 the bony core which represented the antler. Type iv., the 

 highest stage, was represented by the hollow-horned ruminants, 

 in which the horn-shoe was now a permanent feature ; but it 

 was important to note that these animals still shed the first, or 

 earliest, generation of the horny sheath. Horns and antlers 

 were developed alike with a cartilaginous matrix, with subse- 

 quent ossification. These four types were an illustration of 

 onward phyletic evolution, and these stages were still faithfully 

 repeated in the development of the recent species ; this was a 

 clear instance where ontogeny was a shortened recapitulation of 

 phytogeny. — Mr. R. Trimen, F. R.S., communicated a paper by 

 Lieut. -Colonel J. .M. Fawcett, entitled "Notes on the Trans- 

 formations of some South-African Lepidoptera." This memoir 

 was in continuation of one by the same author, already pub- 

 lished in the Society's Transactiotis. It illustrated the earlier 

 stages of thirty-two species, of which six belonged to the 

 Rhopalocera and twenty-six to the Heterocera. — Mr. R. I. 

 Pocock gave an account of a new stridulating organ discovered 

 in the scorpions belonging to the African genus Parabuthus. 

 This organ consisted of a granular sharpened or finely ridged 

 area upon the dorsal side of the seventh abdominal somite and 

 of the first and second segments of the tail. The sound was 

 produced by scraping the point of the sting over these granular 

 areas. — A communication from Dr. R. Broom, on the organ of 

 Jacobson in the elephant-shrew, was read, in which the author 

 showed that the organ of Jacobson, which in Erinaceus was of 

 the Eutherian type, was in Macroscelides marsupial in all its 

 details, and was most nearly comparable to that of Perameles. 

 Pointing out that in the allied genera Petrodromus and Rhyn- 

 chocyon marsupial characters had been discovered by Parker in 

 the skull, the author concluded that Macroscelides was "a very 

 near relation of the marsupials, and had probably little affinity 

 with the more typical insectivores. " Dr. Broom noted that 

 Macroscelides had a discoidal deciduous placenta, and that its 

 young were born in a well-developed condition — A communi- 

 cation from Mr. Frederick Chapman contained an annotated 

 list of the collections of Foraminifera and Ostracoda made by 

 Dr. C. W. Andrews on Cocos Keeling Atoll in 1898.— Mr. 

 G. A. Boulenger, F. R.S., described three new species of fishes 

 from the French Congo under the names Allabcmhelys longi- 

 Cauda (gen. et sp. nov. ), Labeo hikulae (sp. nov.) and C hilo- 

 chromis duponti (gen. et sp. nov.). 



Entomological Society, March 19.— Dr. F. Du Cane 

 Godman, F.R.S., vice-president, in the chair.— Mr. W. J. Kaye 

 exhibited a number of insects from British Guiana, many of them 

 taken by himself, illustrative of Miillerian mimicry. Dr. DuCane 

 Godman remarked that in these regions many different forms of 

 the same butterfly would often occur within a radius of fifty miles, 

 showing a wide range of variation. — Prof. E. B. Poulton, F. R. S. , 



NO. 1693, VOL. 65] 



exhibited cocoons of Malacosoma netistria collected by Mr. 

 Hamm in 1900, spun upon black-currant and apple-trees in his 

 garden at Oxford. All of thett> had been attacked by birds 

 through the leaf, this being the thinnest part of the cocoon, and 

 the pupa thus moreeasily abstracted. With regard to the resting 

 habit of Hybeyiiia leucop/iearia, he said that Mr. Hamm had 

 observed that this moth usually rested in a horizontal position. Dr. 

 Longstaffe said that all the specimens he had observed on green 

 stems affected a similar position, and that he had only found one 

 on a birch. tree. Mr. M. Jacoby said that he never found the 

 species on oak at all, but on palings, also in the same position, 

 which facts Prof. Poulton said tended to show that the protective 

 instinct of the species was retained in such localities. — Mr. G. T. 

 Porritt exhibited two bred black Latrttiia nttiltistrigayia from 

 Huddersfield, and said that the dark form was rapidly increasing 

 in Yorkshire. Of those already emerged and reared from the 

 same brood, three were normal and two dark. — Dr. Frederick A. 

 Dixey read a paper, illustrated by lantern slides, entitled, 

 " Notes on some cases of Seasonal Dimorphism in Butterflies, 

 with an account of Experiments made by Mr. Guy A. K. 

 Marshall." He said that he had long since formed the opinion 

 that Calopsilia ctocalc. Cram., was specifically identical with C. 

 ;!*0OT0Ha, Fabr., and had suspected that the differences between 

 them might prove to be seasonal in character. The belief in their 

 specific identity was held by Piepers and by de Niceville, 

 neither of whom, however, thought that the dimorphism thus 

 shown had any relation to the seasons. Colonel Verbury said that a 

 temporary rainfall in a dry season in dry places had a marvellous . 

 effect in producing intermediate and wet-season forms. Mr. F. 

 Merrifield pointed out the difference between experiments upon- 

 tropicaland European species. In the tropics there are not any 

 very great distinctions of seasons and temperature, whereas in , 

 temperate climates the seasons are clearly marked off from one 

 another. Prof. E. B. Poulton expressed his opinion that by 

 breeding species through, Mr. Marshall had proved that one 

 foim gives rise directly to the other, the pairing of the two forms 

 being a biological test of very considerable value. Colonel 

 Swinhoe, Dr. Jordan and Dr. F. DuCane Godman also joined 

 in the discussion. — Prof. Poulton, F. R.S., read a paper on 

 mimicry illustrated by the SangerShepherd three-colour process, 

 supplementary to his paper read at the meeting of the Society 

 on March 5. 



Mineralogical Society, March 25. — Dr. Hugo Mliller, 

 F.R.S., president, in the chair. — Mr. G. T. Prior contributed 

 a paper on the petrology of British East Africa, the result of 

 examinations of the collection of rock specimens made by Prof. 

 T. W. Gregory during his expedition to Mt. Kenya and Lake 

 Baring in 1892-3, and of collections from the Uganda 

 Protectorate made recently by Sir Harry Johnston. Descriptions 

 were given of the three main groups of rocks, viz., the basement 

 Archcean gneisses and schists, the Palaeozoic shales and sand- 

 stones and the Tertiary volcanic rocks. The gneisses and schists - 

 are associated with dykes both of acid pegmatites and of basic 

 diabasis and epidiorites, and also with granulitic rocks analo- 

 gous to the Charnockite series of India and Ceylon. Of the 

 Palaeozoic Karagwe series a collection of ferruginous shales and ' 

 siliceous schists from Unyoro was described. These rocks . 

 present striking similarities with those of Hatch's Hospital HiH 

 series of the Transvaal and with rocks from the Ingwenyaberg, 

 Swaziland, and a correlation between the Karagwe series and 

 the Cape System of the Transvaal was suggested. The volcanic 

 rocks consist mainly of soda-rich phonolitic rocks which have 

 resulted doubtless from a nepheline-syenitc magma. The lavas 

 from the volcanoes of the Great Rift Valley and of Mt. Kenya 

 and the region between are characterised, like those of the Canary 

 Islands and the Azores, by the prevalence of anorthoclase, by 

 the large amount of soda-amphiboles (cossyrite, catophorite, 

 arfvedsonite) as well as of soda-pyroxenes and by the 

 absence of sphene and noseau. They form a remarkable 

 example of a rock-series showing a gradation in composition 

 from basic phonolites, containing nepheline both in large 

 phenocrysts and in the groundmass, through phonolitic trachytes 

 containing no recognisable nepheline, to phonolitic quartz- 

 trachytes, and finally to acid riebeckite-rhyolites containing 

 much quartz. The later eruptive rocks from Mt. Elgon and 

 the western side of the Great Rift Valley present some points of 

 distinction with the earlier erupted rocks. They are generally 

 of a more basic character like ihose of Kilimanjaro as compared 

 with those of Mt. Kenya. Another point of distinction is the 

 presence in them of titanic acid in large amount, in the form of 



