594 



RODENTIA 



t:^ 



blackish. The individual haii's are slate-grey at base, those of 

 the uuderfur with a sub-terminal band of grey No. 10 about 

 2 mm. in width and a minute blackish tip, the longer hairs 

 blackish throughout. On rump and outer surface of hind legs 

 the pale grey is replaced by light buff. Sides of body and outer 

 surface of fore legs white, the line of demarcation well defined 

 though not remarkably so, and extending along lower portion of 

 cheeks and over base of whiskers to sides of muzzle, the lips thus 

 entirely white and sharply defined against the narrow grey 

 muzzle. A very narrow black eye-ring. Ears blackish, frosted 

 with greyish white, not much contrasted with surrounding parts. 

 Underparts in one specimen white, in another pale cream-buff 

 rather sharply defined from the narrow white area along sides. 

 Feet bufly white, including hairy portion of sole. Tail light 

 cream-bufi', the upper surface sprinkled with blackish hairs along 

 median region. 



Shill. — Apart from its much smaller size (approximately as 

 in Apodemiis flaviroUis) the skull 

 differs from that of Cricefus cricctus 

 in its generally less modified, more 

 murine appearance. Dorsal profile 

 sligiitly and evenly convex through- 

 out. Brain-case relatively narrower 

 and rostrum relatively broader than 

 in Apodemus flavicollis and A. sylva- 

 ticus, but these peculiarities not 

 carried to the same extreme as in 

 Criceius cricetus. Brain-case dis- 

 tinctly longer than broad, slightly 

 wider than deep, smoothly rounded 

 off at sides, the occiput scarcely 

 oblique, so that condyles are not 

 visible when skull is viewed from 

 above ; the general form of brain- 

 case essentially as in Apodeimis sylva- 

 ticus but nari-ower and deeper, and 

 with condj'les more projecting. Interparietal about as in 

 A. sylvaficus, but more convex in front and more nearly straight 

 behind. Interorbital region about as wide as rostrum, its sur- 

 face with faintly indicated median longitudinal groove, its edges 

 slightly ridged. Rostrum a little less than half as wide as brain- 

 case, distinctly more robust than in Apodemus sylvaticus, but 

 without any special peculiarities of form. Nasals tapering 

 gradually backward, squarely truncate posteriorly, much exceeded 

 by nasal branches of premaxillaries. Zygomata slender, not very 

 widely spreading, their middle portions approximately parallel. 

 Auditory bullae moderately lai'ge, essentially as in Apodemus 

 sylvaticus. Mesopterygoid space parallel-sided, about three 

 times as long as wide, its anterior termination nearly in line 



Fig. 117. 



Cricetulus atticus. 



