S60 



Rostrum deepened anteriorly so that dorsal profile is nearlj- 

 horizontal throughout. Upper border of plate forming outer 

 wall of infraorbital foramen nearly horizontal and very abruptly 

 rounded off anteriorly, the plate wider in proportion to its height 

 than in Epimys rattus. In other respects the skull closely 

 I'esembles that of E. rattus apart from its larger general size. 

 The auditory bulla; tend, however, to be less inflated and the 

 incisive foramina to be slightly shorter and wider, their posterior 

 border usually not extending quite to level of antei'ior molar 

 mot. 



Teeth. — Incisors as in E. rattus. Molars with number of 

 roots and general size and proportions of crowns as in E. rattus, 

 liut upper teeth showing a greater tendency toward reduction 

 nf tlie outer cusps. First upper molar with distinct cingulum- 

 like ridge at anterior base of crown, 

 this ridge in some specimens showing 

 a tendency to develop one or more 

 minute tubercles ; first lamina notice- 

 ably distorted by the nearly complete 

 suppression of ^3, which is so reduced 

 as to be practically nothing more than 

 an outward prolongation of the outer 

 border of t'2, usually without trace 

 of antero-external re-entrant angle ; 

 second and third lamina essentially 

 as in Epimys rattus. Second upper 

 molar like that of E. rattus except 

 that /9 is greatly reduced in size and 

 completely merged in outer base of 

 /''^, tlie thii'd lamina thus forming a simple biconvex terminal 

 lieel. Third upper molar essentially as in Epimys rattus, t\ 

 equally well developed, but other elements of tooth less distinct, 

 liower molars differing from those of Epimys rattus in the less 

 evident tendency to develop supplemental tubercles at outer 

 extremities of spaces between the lamime, such rudiments of the 

 small tubercles as may be present usually appearing as slight 

 thickenings at outer extremities of the laminR". 



Measurements. — Adult male from Cortachy, Forfar, Scotland : 

 head and body, 22G ; tail, 179 ; hind foot, 41-^) ; ear, 20. Adult 

 male from Cambridge, England : head and body, 242 ; tail, 185 ; 

 hind foot, 42. Adult male from Tiverton, Devonshire, England : 

 liead and body, 238; tail, 212; hind foot, 42; ear, 21. Adult 

 male from Roydon, Norfolk, England : head and body, 2-50 ; 

 tail, 218 ; hind foot, 45. Adult male from Hampton, neai' 

 London, England : head and body, 255 ; tail, 187 ; hind foot, 41 ; 

 ear, 20 • 5. Adult male from Kilmanock, ^yaterford, Ireland : 

 head and body, 242 ; tail, 209 ; hind foot, 44 ; ear, 20. Adult 

 male and female from Upsala, Sweden : head and bod\', 250 and 

 252 : tail, 18.3 and 183; liind foot, 41 an.l 41. Adult male and 



J-p! 



