ZOOLOGY. 381 



seu aud Ordnimgeu des Tbierreichs," has beeu coutiuued and a 

 number of parts issued during tlie past two years. Trouessart's cata- 

 logue of all the living and extinct species has also been continued in the 

 " Revue et INfagasin de Zoologie." The most important of the many 

 memoirs on special groups is Allen's on the Pinnipeds of North America, 

 which contains besides a revision of those of other parts. The teeth 

 have been examined partly as to their mechanical and i)artly as to their 

 taxonomic relations, by Hensel and Ryder. 



The placentse of Edentates of the families of Dasypodidae and Bra- 

 dypodida? have been examined by Milne Edwards and Joly, — the former 

 by Edwards and the latter by Joly. 



O has made a special investigation of the muscle of the eye iu 



the apes and monkeys. The foramina of the base of the skull have been 

 again investigated with reference to systematic values by Cope for the 

 ^Eluroid Carnivores and by Wingie for the Insectivores. 



THE PROGENITOES OF MAMMALS. 



The parents of mammals have been chiefly sought for iu recent times 

 among the early reptiles, and it has been sup[)osed that they were 

 descended from forms closely related to the Dinosaurians of the Jurassic 

 and Cretaceous epochs. In a recent memoir on the characteristics of 

 the pelvis in the mammals, Professor Huxley has challenged this view,* 

 and has expressed his belief that "it appears to be useless to attempt 

 to seek among any known Sauropsida for the kind of pelvis which 

 analogy leads us to expect among those vertebratod animals which 

 immediately precede the lowest known Mammalia ; lor, if we prolong 

 the series of observed modifications of the pelvis iu this groui) back- 

 wards, the 'Promammalia' antecedent to the Monotremes may be 

 exi)ected to have the iliac and obturator axes i)erpendicular to the 

 sacral axis, and the iliopectineal axis parallel with it; something, in 

 short, between the pelvis of the OrnithorJnjnchus and that of a land 

 tortoise; and provided, like the former, with large epipubes intermediate 

 iu character between those of the lower mammals and those of croco- 

 diles." As this condition is not fulfilled in the Reptiles, Professor 

 Huxle^"^ thinks that the original mammals have descended from an 

 entirely different stock. He asserts that in such a pelvis as the sala- 

 mander, for exami^le, " we have an adequate representation of the tyi)e 

 from which all the different modifications which we find iu the higher 

 vertebrata may have taken their origin." He therefore deduces the 

 conclusion that mammals have been derived from the Amphibians 

 through "some unknown 'promammalian' group, and not from anj 

 known forms of Sauropsida." In corroboration of this view he adduces 

 the two condyles of the occipital of the skull in which the mammals are 



* Huxley (T. H. ). On the Characters of the Pelvis in the Mammalia and the Conclu- 

 sions respecting the Origin of Mammals which may be based on them. Proc. EoyoA 

 Societi/, vol. xxviii, i)p. 395-405, pi. 8. 



