mam:\ialia. 
25 
genera Sorex (Wagl.), Crossojms (Wagl.), Brachysorex (Duv.), 
Crocidura (Wagl.), Pachyura (Selys-Longch.), Diplomesodon 
(Brdt.)*. Types of all tliese subgenera f have been examined ; 
and tlie dentitions of the following species are described in 
detail : — vulgaris j S. pygmceuSj Crossopus fodienSj Crocidura 
leucodon, Croc, aranea^ Croc, suaveolcnsj Pachyura etruscaj P, 
indica, Diplomesodon pulchellus. 
It wasj of course^ a point of the greatest importance to trace 
the sutura maxillo-intermaxillaris, which, in fullgrown examples, 
generally entirely disappears. The author had the good fortune 
to find a nest with young shrews [S. vulgaris) j which were 
still naked and blind. All the bones of the skull, and especially 
the intermaxillaries, were easily separated. The teeth were 
complete in number, though but little developed and still 
covered by the gingiva ; of the five small lateral teeth, three 
belong to the intermaxillary, and two to the maxillaiy, so that 
the dental formula of the subgenus Borex J may be given thus : 
+ I + = 32. That is, eight incisors above and two 
below — the two upper front incisors being large, the six others 
lateral, gradually decreasing in size ; two canines above and 
below; taking the first tooth behind the intermaxillary suture as a 
canine tooth, notwithstanding its very small size, the second must 
be regarded as lower canine tooth on account of its form (it is coni- 
cal, unicuspid) and position ; then follows in the maxillary a 
very small tooth, a premolar, to which corresponds in the lower 
jaw a i)rcmolar which is strongly developed and provided with 
two cusps and two roots ; then follow four true molars above, 
and three below. All the lower molars are twp-rooted. The 
first upper molar has three roots, like the last ; the two others 
are four-rooted. The first upper molar is the strongest of all, 
as in Carnivora, and may be designated as fiesh-tooth. The 
author examined thirty-seven adult examples of Sorex vulgaris 
from St. Petersburg, the Amur-countries, Caucasus, Ural, 
Sitcha, Kamtschatka, Bessarabia, and Unalaschka, and five 
specimens of Borex pygmccusixom Kamtschatka, Amur-countries, 
and the Ural. 
The differences in the dentition between these two species are 
very small ; and the following characteristics of the dentition of 
Borex may be given : — Lower incisor with four prominences 
(corresponding to the number of upper incisors), upper front 
incisors with an exceedingly strong tooth-like lateral tubercle. 
* Gray lias separated Crocidura mria under the name of Myosorcx\ the 
third tooth of the lower jaw is provided with three tubercles. 
t The author has had’ the opportunity of examining Brachysorex during a 
visit to the London and Paris Museums in 1866, subsequently to the publica- 
tion of this treatise. His observations on this subgenus are embodied in this 
abstract, although not contained in the original memoir. 
% In the subgenera of Sorex only the small lateral teeth vary in number, 
the number of all the other teeth fcing constantly the same. The mandible 
has always twelve teeth. 
