Prof. A. Nehring on Myodes lemmus crassidens. 297 



with them. The cheek-teeth only appear to be constantly 

 thicker, and the coronoid process broader than in the latter. 

 On account of tlie first feature I have already suggested, 

 in the ' Sitzungsberichte der Berlin. Gesellsch. naturf. 

 Freunde ' of the 2lst of March, 1899, that as the remains in 

 question represent a Portuguese race of the lemming, they 

 should be separated as " var. crassidens. ^^ 



With regard to individual examples, the remains of which 

 were consigned to me in five boxes, I have now to offer the 

 following remarks : — 



No. 1 *. Skeleton of a middle-aged example, obtained by 

 soaking one of Gadow's mummied lemmings. Total length 

 of the skull 29-2, basal length {'' Basilarlange," Hensel) 26-2 ; 

 breadth across zygomatic arches 19"5 ; upper row of cheek- 

 teeth 8"4, lower 8*2 ; condylar length of the lower jaw (see 

 fig. 3, a-c) 19"5, angular length of the same (fig. 3, a~b) 

 20 mm. Humerus, without the upper epiphysis, 16"1 ; ulua, 

 without the lower epiphysis, 17"6 ; radius, without the lower 

 epijjhysis, 14 ; os innominatum 20 ; femur, without the 

 lower epiphysis, 17*8 j tibia, without the upper epiphysis, 

 23'5 mm. 



No. 2 *. Skeleton of another middle-aged example. The 

 above-mentioned epiphyses of the limb-bones remain in place, 

 without, however, becoming fused. This skeleton also has 

 evidently been derived from one of Gadow's mummied lem- 

 mings by soaking. Total length of the skull (shown in our 

 fig. 3) 29"2, basal length 26*5 ; breadth across zygomatic 

 arches 19 ; upper row of cheek-teeth 8" 3, lower 8*0 ; condylar 

 length of lower jar 18'8 mm. Humerus, without upper epi- 

 physis, ln*3; femur, with lower epiphysis, 18*3; tibia, with 

 upper epiphysis, 22*8 mm. 



No. 3. Cranium with lower jaw, to which a number of 

 parts contained in No. 5 presumably belong. Total length 

 of skull 30, basal length 27*2 ; breadth across zygomatic 

 arches about 20; upper row of cheek-teeth 8'5, lower 8'3 ; 

 condylar length 19*5 mm. 



No. 4. Cranium without lower jaw ; but a pair of lower 

 jaws in box No. 5 evidently belong here. Total length 30, 

 basal length 27 ; breadth across the zygomatic arches 20 ; 

 rows of cheek-teeth 8'G mm. 



No. 5. A box containing a badly-preserved cranium, as 

 well as a pair of under jaws ; also anotlier pair of under 

 jaws, probably belonging to No. 4, a much damaged half of a 



• To be exact, only the principal portions of the skeletons lie before 

 me -which are still partly in their natural position, as the dried sinews 

 ren.ain in most cases. See P. Z. S. 1896, p. 304. 



