parts containing 1,264 pages, while fasciculus 

 VI. is devoted entirely to addenda and corri- 

 genda (94 pp.) and a closely printed 3 column 

 index of 109 pages. 



The index has some 16,827 entries indicating 

 that over 16,000 names hâve been listed ; of 

 thèse 2,977 are generic and 13,850 spécifie. 

 The total number of recognized gênera and sub- 

 genera is 1,840 ; of recognized species about 

 7,500. Thèse numbers are significant as an 

 index of progress in the study of mammals. In 

 1758, 39 gênera and 183 species were described 

 by Linnaeus ; in 1798 the total number of 

 recognized gênera was less than 100 of which 

 only 1 was extinct ; while in 1898 the number 

 of gênera and subgenera recognized by Troues- 

 sart is 1,840. This rapid increase in names 

 within the présent century has resulted from 

 the more thorough exploration of ail parts of 

 the globe, more careful study of improved ma- 

 terial, and especially from the marvelous de- 

 velppment in our knowledge of extinct forms. 



Naturally the naming of so many species has 

 presented many difflculties and even a super- 

 ficial examination of the catalogue shows many 

 curiosities of nomenclature. The names vary 

 in length from one to ten syllables, the shortest 

 being Mus rex and the longest Brachydiastema- 

 totherium transsylvanicum. The tendency to re- 

 peat favorite spécifie names in many groups is 

 very noticeable ; major has been applied to 51 

 species, intermedius to 54, robustus to 56, gracilis 

 to 65, and mijior to 71. Many species hâve 

 been named in honor of eminent naturalists ; 

 the zoologists who bave had a dozen or more 

 mammals named after them are : Blanford, 12 ; 

 Allen, Gray and Lartet each, 13 ; Gervais and 

 Owen, 15 ; Geoffroy, 17 ; Gaudry, 20 ; Milne 

 Edwards, 21 ; and Cuvier, 28. 



That such a catalogue necessarily contains 

 some errors is self-evident, but the wonder is 

 that there are not more of them. There are of 

 course omissions (e. g., a genus, subgenus and 



