[Beprinted from SCIENCE, N. S., Vol. X., No. 349, 

 Pages 491-495, Odober 6, 1899.] 



SCIENTIFIO B00K8. 

 Catalogus Mammalium tam viventîum quam foa- 

 silium. By Dr. E. L. Trouessaet. Berlin, 

 R. Friedlânder & Sohn. New éd., fasciculus 

 VI., Appendix and Index, 1899, 8° pp. 1265- 

 1469. Price of complète work 66 Marks. 

 The completion of the great ' Catalogus 

 Mammalium ' which Dr. Trouessart has been 

 publishing in parts during the past two years 

 marks an epoch in systematic work in mam- 

 mals. Previous catalogues, incomplète at best, 

 bave been restricted either to living or extinct 

 forms, so that zoologists bave been obliged to 

 consult one set and paleontologists anotber. 

 But as Professor Osborn has recently re- 

 marked : ' ' Among the vertebrates the sépara- 

 tion of the living and extinct forms is at présent 

 a calamity. Zoologists must become familiar 

 with paleontology whether they prefer to do so 

 or not. It is impossible, for example, to under- 

 stand the modem races of dogs without study- 

 ing the Oligocène races and their ancestors,"* 

 Dr. Trouessart has sought to remedy this defect 

 by bringing together in one list ail the species 

 of mammals, living and extinct, which bave 

 been described between 1758 (the date of publica- 

 tion of the lOth édition of the ' Systema Naturse' 

 of Linnaeus) and the close of the year 1898 — a 

 period covering exactly a century and a half, 

 The first three parts of this catalogue hâve 

 already been reviewed in thèse pages ;f without 

 attempting to treat the others with the same 

 détail, attention may be called to a few points 

 which are suggested more especially by the last 

 brochure. The catalogue proper consists of 5 



*SciENCE, N. S., X., p. 171, August 11, 1899. 

 tSciENCE, N. S., VI., pp. 68-69, July 9, 1897; 

 VII., pp. 30-33, January 7, 1898. 



