1884.] Geology and Paleontology. 717 
GEOLOGY AND PALAZONTOLOGY. 
LYDEKKER ON Extinct MAMMALIA oF Inp1A2—The noble 
ume below named, concludes the first part of the work of Dr. 
Lydekker on the Fossil Mammalia of India. It covers a part of 
the subject which was left very incomplete by Cautley and 
Falconer, and includes much new matter. It adds materially to 
our knowledge of the Mustelidz, Urside, Canidae, Viverride, 
_ Felidæ, and Hyznide. Dr. Lydekker shows that India, in the 
_ late Miocene period, was the headquarters of the genus Hyzna, 
there being no less than five species represented in the collection. 
Of Urside there are five species, viz., two of Ursus and three of 
yenarctus, of which one Ursus and two Hyenarcti are new. 
The latter genus receives thorough treatment, and Dr. Lydekker 
has added greatly to our knowledge of its characters. There are 
four species of Canidæ and nine of Felide. Of the latter, two 
Species are sabre tooths. Two species of Mellivora and one of 
Mellivorodon (gen. nov.) represent the Mustelidz. 
descriptions of the species are thorough, and the plates 
are excellent. Dr. Lydekker exercises a healthy conservatism in 
the Matter of species, and a rather greater degree of the same 
trait in dealing with genera. He is disposed to drop generic di- 
“sions whose characters are not of the highest degree of import- 
To this course we object, that if we begin to neglect 
. omical characters, we end in a disuse of all genera, or in purely 
ty divisions. The only reason for not regarding an ana- 
omical character as a generic definition, is the inconstancy of that 
rın the different individuals of the same species. The 
at of not using such an obvious character as the presence of 
additional digit on the fore foot, is seen in the author’s treat- 
ment of the genus Aceratherium. Having failed to recognize as 
a the steps which separate this genus from Rhinoceros, he 
w fain to confess that the existence of the intermediate forms 
“probably 
Probably 
: chyus, ah Amynodon to this series, and ultimately of Hyra- 
te: ancestor of the line. We have long been of the opinion 
tewon S BO Course open to the systematist, other than the 
3 genealogic, of the structural steps by which the stages of the 
W: cal lines are marked. (See “Origin of Genera, 1868.) 
ioys, Woor justly says that the name Ursus ursinus 1S ridicu- 
Ea f wish those who write Mephitis mephitica, Sialia sialis, 
a take a similar view. The adoption of generic names 
oR ; , 
Re © Vol oF eoin ot th i Gin; Sees, and 
Nathada c.2) OL 1, he Geological Survey of India; s 
Period, carnivora, Vol. 11 Siwalik Caclo rdalidæ, 1883. Vol. i. Additional 
actyla and Proboscidia, a 
Ma 
