OCR Text |
Show 2 LOED LILEOED ON A HTBEID DT7CK. [Jan. 15, of a Platypus (Ornithorhynchus anatinus) received from his former pupil Mr. J. P. Hill, Demonstrator of Biology in the University of Sydney. It illustrated a paper recently read by Messrs. Hill and C. J. Martin before the Linnean Society of N e w South Wales2 The embyro had been obtained from one of two eggs " just ready to be laid," which Messrs. Hill and Martin collected during a recent holiday-expedition in Australia. The eggs measured each 18 m m . by 13-5 mm., and were somewhat larger than those described by Caldwell. Prof. Howes briefly recapitulated the circumstances of the Caldwell and Semon Australian expeditions, and remarked that the same post brought him the photograph exhibited and an author's copy of Prof. Semon's first monograph2 on the development of the Monotremata and Marsupialia, which he laid upon the table. He commented upon the high artistic merit of the photograph, and briefly recapitulated the facts which Messrs. Hill and Martin had already recorded from the study of tbe object itself. H e pointed out that the stage in development which tbe former depicted was intermediate between those thus far described by Semon, and that therefore the facts which it revealed were novel; and remarked that he brought it forward in testimony to the assertion that our countrymen at the Antipodes are doing their best, as opportunity occurs, to protect us against the slur which is being cast upon us, in connexion with the well-known circumstances to which he had sufficiently alluded, Criticising the photograph, he drew attention to the appearances presented by the myelomeres (somatic neuro-meres) as compared with the encephalomeres (cephalic neuromeres), regarded by McClure as homologous sets of structures. The appearances which the myelomeres presented (unless indicative of mere cell-differentiation and localization during development) seemed to him to suggest that they might be compound structures, and that in each 'myelomere' we might be dealing with a product of union of neuromeres of the encephalomeric order, and to therefore raise a question of manifest interest, in its bearings upon the metamerism of the vertebrate body, and upon the recent conclusions of Orr, McClure3, and others concerning the segmental value of the brain and head region. The Secretary exhibited, on behalf of M r . E. Lydekker, F.Z.S., a life-sized drawing of fdiurus zenkeri, a new and remarkably smai! form of Flying Squirrel from West Africa, recently described by Herr Matschie (Sitz.-B. Ges. nat. Freunde, Berlin, 1894, p. 197). The Secretary, on behalf of Lord Lilford, F.Z.S., exhibited the skm of a Duck, believed to be a hybrid between the Mallard (Anas 1 Cf. Proc. Linn. Soc. N. S. W., Nov. 28, 1894 p ii wV'x??1- Fors^hungsrfse T 11 inAustr. u. d. Malay. ArchipeL' (Denkschr. d. Med. JNaturwiss. Gesellsch. Jena, Bd. v. p. 3). 3 Cf. M^ure, Anat. Anzeiger, Bd. xii! p." 435, and Journ. Morph. vol. iv. |