410 MB. G. E. H. BAREETX-HAMJLTON ON [Apr. 3 



applies to some form of Mus sylvaticus 1 . His description is 

 certainly borne out by one of his specimens now in the British 

 Museum of Natural History (no. 45.11.15.17), which, although 

 an old and faded skin, and of little use for a careful and accurate 

 examination of its characters, undoubtedly belonged to a Mus 

 sylvaticus-like Mouse. I cannot distinguish the skull by any cranial 

 or dental characters. The ears and feet of this specimen would 

 appear to be rather shorter than in ordinary examples, as is also 

 the case with the dimensions of two specimens in alcohol from the 

 Gerbe collection as given by Mons. E. Lataste. Lastly, Herr 

 Herluf Wiuge, to whom I wrote for information regarding the 

 specimens in the Danish Museum at Copenhagen, has been good 

 enough to inform 2 me that the Museum possesses four Icelandic 

 specimens of Mus sylvaticus, " two skins and two spirit-specimens, 

 all of them looking very ordinary, quite resembling Danish speci- 

 mens." The measurements sent me by Herr Winge are not 

 smaller than those of average sylvaticus. 



There can be little doubt that the Eield-inouse of Iceland is very 

 close to that of Europe, and can only be regarded as subspecifically 

 distinct. 



10. MUS SYLVATICUS HAYI. 



Mus hayi, Gr. B. Waterhouse, Proc. Zool. Soc. 1837, p. "70. 



Type from Tangier, Morocco, no. 52.9.13.9 (British Museum 

 Collection), in alcohol, from the collection of the Zoological Society 

 of London. 



Nomenclature. Mus hayi Waterhouse is simply Mus sylvaticus of 

 Morocco. 



Distinguishing Characteristics. This subspecies can only be 

 described at present from its negative characters. It is not a 

 large bright Mouse like M. princeps, but its size exceeds that of 

 M. s. intermedins of England, and it has in addition the tail usually 

 longer than the head and body. 



The skull commonly reaches a length of 26 mm. 



Distribution. For the present I am obliged to include under 

 this name the Long-tailed Eield-mice of Morocco, Spain, Portugal, 

 and the neighbouring countries, including those of the Mediter- 

 ranean islands. Of these I have seen specimens from Corsica 

 and Sicily, the latter of which, however, have a name ready for 

 them in Mus dichrurus Bafinesque. 



Later investigations will probably show the existence of more 

 than one subspecies in these regions. Thus some specimens from 

 Villabra, Gralicia, Spain, are small and very red ; they come from 

 a height of 1300 metres, and probably indicate the existence of 

 more than one subspecies in Spain. 



1 Although BitippeH, who seems to have examined the original specimen of 

 Thienemann, has declared it to be a Mus musculus, a piece of information for 

 which I am indebted to Herr H. Winge. 



2 In Hit. of 14th April, 1899. 



