Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/233

 Cricetus songarus.

Upper jaw —

Length. Width.

Diastema 0.30

Molar series 0.19

PM 4 0.07 0.05

M l 0.05+ 0.05-

M 2 0.04- 0.04

Lower jaw.

Diastema 0.18

Molar series 0.17

PM 4 0.07 0.05-

M 1 0.06 0.05-

M 2 00.5 0.04-

EXPLANATION OF PLATE.

Plate VIII.

Fig. 1. Arvicola ratticeps. Upper jaw, lateral aspect.

1 a. Dentition of the upper jaw, magnified six diameters.

1 b. Lower jaw, external aspect.

1 c. The same, internal aspect.

1 d. Dentition of the lower jaw, magnified six diameters.

2. Arvicola Guliemi, n. s., lower jaw, external aspect.

2 a. The same, internal aspect.

2 b. Dentition of the same, magnified six diameters.

3. Lemmus norvegicus (var.), lower jaw, external aspect.

3 a. The same, internal aspect.

3 b. Dentition of the same, magnified six diameters.

4. Lemmus torquatus (var.), anterior part of the skull, lateral aspect.

4 a. Dentition of the same, magnified six diameters.

5. Lepus diluvianus, skull, natural size, lateral aspect.

6. Cricetus songarus, anterior portion of skull, lateral aspect.

6 a. Dentition of the above, magnified six diameters.

6 b. Lower jaw, external aspect.

6 c. The same, internal aspect.

6 d. Dentition of the lower jaw, magnified six diameters.

k2