VALIDITY OF THE YELLOW-NECKED MOUSE. 245 



Mus sylvaticus typicus et Mus sylvaticus ivintoni et Mus sylvaticus 

 princeps* Barrett-Hamilton, ' Proc. Zool. Soc. Lond., 1900, 

 pp. 404-6-8 (plate xxv. fig. 1). Mus flavicollis ivintoni, Millais, 

 in lit. (vide remarks above). 



Description. — A fine and remarkably handsome Mouse, whose 

 general form does not differ from Mus sylvaticus, but easily 

 distinguished from it by the following important characters : — 

 Tail,t as a rule, exceeds, rarely equalling, head and body. 

 Size much larger than Mus sylvaticus. Upper parts a rich 

 yellow-brown, darkening towards the back into a well-marked 

 deep brown inclining to blackish, dorsal streak. Cheeks and 

 sides of body yellowish brown mixed with black, brown, and 

 golden hairs. A well-defined collar (or breast mark) and pen- 

 dant present, of a light yellow, varying considerably in size 

 (usually about 8 mm. broad), in some specimens extending below 

 the front legs. In others, again, the breast band may take the 

 form of an irregular blotch completely covering the breast and 

 even extending to the belly. Throat, below the cheeks, and 

 belly pure white, showing no dark hairs whatever. This is 

 separated from the above parts by a well-marked line of 

 demarcation. Under side of tail covered with white hairs. 

 Measurements (approximate) : — Head and body, 99 mm. Tail, 

 100 to 104 mm. Hind foot, 22 mm. Ear, 14 to 18 mm. Skull 

 considerably larger than that of sylvaticus. 



Eegarding our present knowledge of the range of Mus flavi- 

 collis as far as Britain is concerned, it seems local in its distri- 

 bution, but occurs commonly where it is found. Even in a 

 district where it is common it is restricted, I have found, to 

 certain areas. I have known one spot, about an acre in extent, 

 where I was pretty certain of finding these Mice. 



Flavicollis, up to the present, is recorded from Hereford, 

 Northampton (De Winton), Suffolk (Tuck), Essex (Laver), 

 Gloucestershire (Jeffreys), Sussex (Millais), and Surrey {ipse et 

 Messrs. Mouritz and Dent). It doubtless occurs in many other 



* Mus s. princeps I cannot regard otherwise than a fine and typical 

 Mus flavicollis. 



f For a full description see De Winton's paper, ' Zoologist,' 1894. This 

 volume may not be available to all naturalists, and for the convenience of 

 these I again describe it. 



