APODEMUS 



791 



Sub-Family MURINE. 

 1857. Murines Baird, Mamm. N. Amer., p. 434 (part). 



Geographical distribution. — Originally confined to the Old 

 World south of or barely entering the Arctic region, but 

 members of two genera now everywhere artificially distributed. 



Characters. — Molars tuberculate, brachyodont, rooted, the 

 tubercles of the maxillary teeth arranged in three primary 

 longitudinal rows ; external form with no special modifications. 



Remarks. — The sub-family Murinse contains about fifty 

 described genera, five of which occur in Europe. 



KEY TO THE EUROPEAN GENERA OP MURINE. 



Mesopterygoid fossa reduced to a triangular space 

 scarcely extending in front of hamulars ; coronoid 

 process of mandible obsolete ; back densely and 



conspicuously spinous (Crete) Acomys, p. 883. 



Mesopterygoid fossa normal, extending decidedly in 



front of hamulars, its sides usually parallel or 



nearly so ; fur not spinous, though back sometimes 



with inconspicuous flattened bristles (Distribution 



.general). 



First and second upper molars with two tubercles on 



inner side. 



Upper incisor with outer side of cutting edge entire ; 



first upper molar 5-rooted, its crown not so 



long as that of re 2 and m? combined ; size 



large (House-rats) Epimys, p. 848. 



Upper incisor with outer side of cutting edge broken 



by conspicuous notch and projection ; first upper 



molar 3-rooted, its crown longer than that o£ 



m? and m? combined ; size small (House-mice) Mus, p. 863. 



First and second upper molars with three tubercles on 



inner side when unworn. 



Tail not prehensile, completely haired at tip ; ear 



without lobe closing meatus ; rostral portion of 



skull normally developed, the length of diastema 



noticeably greater than depth at front of m 1 



(Field-mice) Apodemus, p. 791. 



Tail prehensile, naked at tip above ; ear with con- 

 spicuous lobe closing meatus ; rostral portion 

 of skull so shortened that length of diastema is 

 less than depth at front of m 1 (Harvest-mice)... Micromys, p. 840. 



Genus APODEMUS Kaup. 



1829. Apodemus Kaup, Entw.-Gesch. u. Naturl. Syst. Europ. Thierwelt., 



I, p. 150 (agrarius). 

 1857.- Mus Blasius, Saugethiere Deutschlands, p. 309 (part). 

 1905. Micromys Thomas, Ann. and Mag. Nat. Hist., 7th ser., xv, p. 492, 



May, 1905 (part). 

 1908. Apodemus Thomas, Ann. and Mag. Nat. Hist., 8th ser., I, p. 447, 



May, 1908 (part). 



Type species. — Mus agrarius Pallas. 



Geographical distribution. — Northern temperate portion of 



