MAMMALS PttdM JUGOSLAVIA. ' 861^ 



Description. The dorsal fur is fl. lighter shade of yellow than 

 that usually seen in more northerly Bpecimens. The belly colour 

 is wl lite, often with the slaty bases ot the ventral hairs readily 

 perceptible ; in three specimens there are traces of yellowish 



WHish. 



The skulls show the chai-acteristic shoi't brain-case and arc- 

 like zygomas of M. a. arvalis. 



MiCROTUs AiivAHs LEVIS Miller, 



TyjJC locality. Rumania. 



Mat>',rial examined and Dimensions. Two young adults (1 J , 

 1 $) collected by Montagu and Cotton in June 1923 in Bled, 

 Slovenia. One young adiilt(<5') collected by Montagu in Julie 

 1923 in Kupjak, Croatia. 



1)I,ED, 



47. Young adult S, 16.6.23. 

 305. „ „ ?,16.G.23. 



Kupjak. 

 55. Young adult <?, 26.6.23. 



Desorijytion. The dorsal brown coloration of the skins is 

 noticeably bright. In each example, and particularly in No. 47, 

 this brightness is present also on the flanks in such a manner as 

 to form a line of demarcation mote definite than is usual in 

 M. arvalis. The belly is silvery without yellow wash. The feet 

 are nearly seal-brown. 



Tlie skulls of these specimens are those of typical M. a. levis, 

 showing the characteristic long brain-case and straight parallel 

 zygomas. 



MiCEOTUS AKVALIS CALYPSUS, Subsp. n. 



Type locality. Nova Varos, Serbia.. 



Material examined and Dimensions. One adult ( J ?) collected by 

 Martino in June 1921 in Nova Varos. 



HB. T. HP. E. 



2>pe 219. Adult <? ?, 13. 6. 21 101 38 15 11 



Description. The dorsal colovir is pale yellow, distinctly lighter 

 than that of M. a. arvalis, slightly overlaid with grey in a median 

 line. The ventral surface is clear silver. The feet are whitish 

 yellow and the tail hi colour, dorsal ly seal-brown, ventrally 

 whitish yellow. 



Tlie size of the skull and hind feet resembles in its smallness 

 M. a. arvalis rather than M. a. levis. 



The skull shows the remarkable combination of a long brain- 

 case and arc-like zygomas. In other respects it is not peculiar. 



Proc. Zool. Soc— 1923, No. LVII. 57 



