anterior parts of two skulls, and two rami of lower jaws of a small species of Cricetus which so closely resemble those of Cricetus songarus, though very slightly larger than the specimens we have compared them with, that we must, for the present at least, refer them to that species. It is possible that this is the same species as that described by M. Pomel, from the Breches de Coudes, as Cricetus musculus. Cricetus songarus at present inhabits Russia and western Siberia.
Measurements.
Lepus diluvianus.
Basal length of skull from foramen magnum to anterior portion in. of intermaxillary 3.42
Extreme length 4.36
Height of skull from alveolar border of M 1 to highest part of frontal 1.54
Width, extreme, at squamosals 2.00 Basal length of basioccipital 0.56 " " basisphenoid 0.56 " " basisphenoid 0.32 Length of suroccipital 0.58 Width " " 1.10 Length of parietals 0.96 Width " " 1.23 Length of frontals 1.71 Width of frontals (double the half) 1.31 Length of nasals 1.49 Width of nasals (extreme) 0.90 " " (minimum) 0.83 Width of malar 0.40 Malar process of maxillary to posterior end of malar 1.43 Diastema between incisors and PM 2 l.27 Molar series - 0.77
Lower jaw — Total length, not including incisor 2.76 Depth at M 1 0.62 Depth from condyle to angle l.90 Length of diastema 0.89 Molar series - 0.75
Width. Length, in. in.
Dentition, upper PM 2 0.16 0.08
PM 3 0.22 0.12
PM 4 0.25 0.11
M 1 0.24 0.13+
M 2 0.20 0.11
M 3 0.09 0.05
lower PM 3 0.12+ 0.16
PM 4 0.15 1.12
M l 0.14 0.14
M 2 0.14 0.12+
M 3 0.10 0.10
VOL. XXVI. PART I.
