1869.] Zoology. 473 



12. ZOOLOGY— ANIMAL MOEPHOLOGY AND PHY- 

 SIOLOGY; AND PtECENT LITEEATUEE. 



MoEPHOLOGY. 



New Views on the Homologies of the Suspensorium. — The ad- 

 vanced school of osteologists — that is to say, those who reject the 

 vertebral theory of the skull — originated by Oken and Goethe and 

 developed by Carus, have been in the habit of pointing to the 

 ossicula auditus as the homologues of the quadrate and articular 

 pieces, the incus being regarded as the homologue of the former, the 

 malleus as that of the latter. The relations of the chorda tympani 

 to these bones, though said to support this interpretation, did not 

 really do so ; and many powerful arguments were urged against it 

 by Professor Peters of Berhn, Professor Humphry of Cambridge, 

 and others. Professor Huxley, who is chiefly responsible for the 

 view in this country, has re-examined the matter, and has been led 

 to a much more satisfactory conclusion, especially from the study 

 of that very remarkable hzard, the Hatteria, rhyncocephalus, or 

 Sphenodon of New Zealand. Instead of now regarding the incus 

 as the homologue of the quadrate, he considers it to form part of 

 the second visceral arch, and to be represented in Ends and Eeptiles 

 by a hgament or a cartilage connected with the stapes. He regards 

 the malleus as the representative of the quadrate, the articidare of 

 the lower Vertebrata not being represented by bone in the Mam- 

 maha. In Fishes he considers the incus to be represented by the 

 " hyomandibular " or " suspensorial " element. Mr. Parker, the 

 author of the very splendid volume on the Shoulder Girdle issued 

 last year by the Eay Society, has been examining this question of 

 the lower jaw in Amphibians, and his researches lead him to agree 

 with Professor Huxley's conclusions. 



Muscidar Homologies. — There are some important papers rela- 

 ting to this subject to be chronicled. Professor Eolleston, in a paper 

 read to the Linnean Society, discusses the homology of certain 

 muscles connected with the shoulder-joint ; and in the Transactions 

 of the same Society are very well-illustrated memoirs on the limb- 

 muscles of the Six-banded Armadillo, and of the " Ard Vaak," or Cape 

 Ant-eater. These three papers emanate from the Oxford Anatomi- 

 cal Laboratories. Professor Humphry has two papers on similar 

 subjects (Myology oi Pteropus, and of the Leg and Forearm) in the 

 ' Journal of Anatomy ;' whilst Dr. Macahster, of Dubhn, has a third, 

 on the Pronator Muscles in Vertebrate Animals. The general result 

 of these papers is greatly to add to our knowledge of the muscular 

 structures of Mammalia, and especially to give definite views on the 

 serial homologies of the muscles of the fore and hind extremities. 



