80 Miscellaneous. 
nearly all parts of the body the fur is bicoloured, dusky at its roots 
for two-thirds of its length ; on the upper parts the dusky colour 
becomes almost black, and on the under much paler. From the 
chin to the space between the fore legs is an elongated patch of fur 
which is pure white from root to tip, just as in Hesperomys atro- 
gularis. The tail is deep dusky above, paler below; claws white. 
In the outline of the grinding-surfaces of the molar teeth, this 
species differs from all others at present described. Without en- 
tering into a minute description of these teeth, of which it is difficult 
to give a clear idea without figures, it may be stated that they have 
somewhat the same arrangement of cusps as those of N. cinerea of 
Baird, saving that in the present species the anterior cusp or prism 
of the first tooth in the lower jaw is in a position decidedly outside 
the line of the cusps of the other teeth. The exposed ends of what 
I have termed the prisms of these teeth constitute their grinding- 
surface, which, instead of having an angular outline as in NV. cinerea, 
present, as in those of V. floridana, a series of transverse, ovoid or 
loop-like figures; but these loops in the present species are much 
narrower in an antero-posterior direction than in any other species, 
owing to the folds of enamel entering more deeply and broadly into 
the sides of the tooth. 
Length of the head and body ............ 6 6 
of the head: v:.aageshes eiliat aig Lig 
of the edfe tic). wusu pests es 0 8 
of the foreearmic:|. 24444 7iaks elas 1 3 
——— of the fore foot and claws...... ... 0 8 
of the ibid. 1: Ooi 'we eam ges er 
of the tarsus and toes ............ bid 
OF tad 5. doe sit ads Soha 6 0 
Breadth of the ears: | a.% 45% sais vost io oe 0 8 
of the hind feet at the root of the 
inner tO. isa 54 SRE EES bee 0 3 
Length of the skull from the front of the nasal 
bone to the occipital crest............ La Be 
Breadth across the zygomatic arch ........ 0 11 
Length of the nasal bones: ............... 0: 81 
from the point of the upper incisor to 
_ the crown of the first molar .........: OaGe 
of the molar series? 4:1... 00% oe 0 4 
Length of the incisive foramina .......... 0 4 
~ of the palates. 20... 220. ieee 
Breadth of palate between two front molars... 0 14 
-- of palate between two posterior molars 0 2 
Length of lower jaw from point of incisors to | 
condyle 2. + 2). lle Vie betel vane aati | Oe 
Depth from coronoid process to the angle.... 0 6 
Proc. Zool. Soc. June 25, 1861. 
