Irish Mani77ials. 87 



Ireland, we come to the L,ong- tailed Field-mouse {Mus 

 sylvaticus), which Mr. Lydekker not inappropriately calls the 

 Wood-mouse, to distinguish it from the Voles, which are 

 usually known as "Field-mice." Among the characters 

 of this species which distinguish it from the House-mouse are 

 the mammae, which number six, as opposed to ten in M2is 

 viusculus. The tail of this species is often quite as long as, or 

 longer than, the head and body, and the skull is distinguish- 

 able from that of the House-mouse. 



Mr. I^ydekker includes in his work a supposed species of 

 Mouse, recently added to the British list by Mr. W. K. 

 De Winton,' viz., the Yellow-necked Mouse {Mus flavicollis of 

 Melchior). Although we do not wish to judge too hastily of 

 Mr. De Winton's discovery, we are inclined to think that this 

 supposed species is merely a very fine and handsome variety ^of 

 M. sylvaticus, and we question Mr. I^ydekker's wisdom in 

 hastening to include it in the British list. Mr. De Winton's 

 characters laid down for this Mouse seem to us to be very 

 insufficient, considering that it occurs everywhere with AIus 

 sylvaticus ; although the case might, we admit, be different 

 were the geographical area inhabited by Mus flavicollis clearly 

 defined. We are indebted to Mr. De Winton for kindly per- 

 mitting us to examine his fine series, and we have carefully 

 compared them with those of specimens in our own collection, 

 and we confess that we cannot see where Mus sylvaticus ends 

 and M, flavicollis begins. 



The Black Rat {Mus rattus), says Mr. lyydekker, quoting from 

 Mr. J. K- Harting, "must now be regarded as very rare" in 

 Ireland. In fact it may be said to be confined entirely to the 

 seaport towns, the Black Rats which are recorded from inland 

 localities having invariably in our experience proved to be 

 examples of Thompson's M21S hibernicus. We have seen 

 specimens of the true Black Rat taken in recent years at 

 Waterford and Belfast, but its presence at these towns is by 

 no means constant, and appears to be entirely due to its having 

 been brought there, sometimes in numbers, by foreign ships. 

 The variety known as Mus Alexafidrifius has been taken in 

 a corn ship at Belfast, and a specimen is in the Museum of that 

 city.= As regards the introdiiction of the Black Rat into 



1 Zoologist, Dec, 1894, p. 441. * Irish Sportsman^ Dec. 19th, 1891. 



