492 SCIENCE. 
consult one set and paleontologists another. 
But as Professor Osborn has recently re- 
marked: ‘‘ Among the vertebrates the separa- 
tion of the living and extinct forms is at present 
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 modern races of dogs without study- 
ing the Oligocene races and their ancestors.’’* 
Dr. Trouessart has sought to remedy this defect 
by bringing together in one list all the species 
of mammals, living and extinct, which have 
been described between 1758 (the date of publica- 
tion of the 10th edition of the ‘Systema Nature’ 
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 have 
already been reviewed in these pages ;+ without 
attempting to treat the others with the same 
detail, attention may be called to a few points 
which are suggested more especially by the last 
brochure. The catalogue proper consists of 5 
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 have been listed; of 
these 2,977 are generic and 138,850 specific. 
The total number of recognized genera and sub- 
genera is 1,840; of recognized species about 
7,500. These numbers are significant as an 
index of progress in the study of mammals. In 
1758, 39 genera and 183 species were described 
by Linnaeus; in 1798 the total number of 
recognized genera was less than 100 of which 
only 1 was extinct ; while in 1898 the number 
of genera and subgenera recognized by Troues- 
sart is 1,840. This rapid increase in names 
within the present century has resulted from 
the more thorough exploration of all parts of 
the globe, more careful study of improved ma- 
terial, and especially from the marvelous de- 
velopment in our knowledge of extinct forms. 
Naturally the naming of so many species has 
presented many difficulties and even a super- 
ficial examination of the catalogue shows many 
*ScrENCE, 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. 
[N. S. Von. X. No. 249; 
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 specific names in many groups is 
very noticeable; major has been applied to 51 
species, intermedius to 54, robustus to 56, gracilis 
to 65, and minor to 71. Many species have 
been named in honor of eminent naturalists ; 
the zoologists who have 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 
5 species of phyllostome bats described by 
Miller in the Proceedings of the Philadelphia 
Academy Science, in July, 1898) ; errors in the 
authority of genera and species and in the au- 
thors of papers (e. g., in crediting Bailey’s ‘ List 
of Mammals of the District of Columbia’ to 
Bangs); adoption of the wrong names for groups, 
thus differentiating forms which are identical 
while reducing others to synonomy which are 
really distinct. But the care which the author 
has taken to eliminate errors of all kinds is 
shown by the voluminous appendix of 94 pages 
devoted to corrections and additions of genera 
and species which were omitted, or which have 
been described during the two years in which 
the catalogue has been passing through the 
press. 
The most serious defect in the catalogue 
seems to be in the treatment of genera. Refer- 
ences are so seldom given that it is difficult to 
consult the original descriptions. Moreover the 
2,977 generic names indexed probably do not 
represent much more than 65 per cent. of those 
actually published, so that in some cases names 
which have the best claim to adoption are not 
even mentioned. It should be stated that the 
author’s aim has been to adopt the best known 
or most generally used name for a genus, on the 
plea that the work would thus be more gener- 
ally useful—in short he has in many cases fol- 
lowed the auctorum plurimorum rule rather than 
the law of priority. He has thus been led to 
