THE ZOOLOGIST 



No. 216.— December, 1894, 



ON A NEGLECTED SPECIES of BRITISH FIELD MOUSE, 

 MUS FLAVICOLLIS, Melchior. 



By W. E. DE WlNTON. 



This species of Field Mouse, described in 1834 by Prof. 

 Melchior, of Copenhagen, on page 99 of his work on Danish 

 and Norwegian Mammals,* has hitherto been disregarded by 

 British naturalists, although several writers, under Mus sylvaticus, 

 have mentioned that " a larger variety measuring 4j inches, 

 exclusive of the tail, is sometimes found in woods" ;t but beyond 

 this they do not go. Field Mice answering the description of 

 Melchior's flavicollis, being abundant in some of our English 

 counties, I think this animal should find a place in the list of 

 British mammals ; and for my part I quite agree with Melchior 

 that it is a perfectly distinct species, since, apart from its size 

 and colour, the special characters of the skull, hereafter to be 

 described, sufficiently entitle it to that rank. 



In the first place I will describe its outward appearance, and 

 show how it can be distinguished from Mus sylvaticus. 



The full-grown animal measures as follows : — Head and body, 

 108 to 115 mm. Tail, 108 to 115 mm. (the greater measure- 

 ments not necessarily belonging to the same animal, but the head 

 and body and tail measurements of each individual will generally 

 be found within 5 mm. of one another, sometimes the head and 

 body, sometimes the tail, giving the longer measurement). Hind 



* ' Den danske Stats og Norges Pattedyr,' 8vo, pp. xvi. 298, pig. 13. 

 f Cf. Jenyns, Man. Brit. Vert. An. 1835, p, 31. 



ZOOLOGIST, THIRD SERIES, VOL. XVIII. — DEC. 1894. 2 M 



