640 



MILLER 



Fig. 40. Dasymys rufidus. Type. 

 Natural size. 



Dasyjnys rufulus (fig. 40) differs chiefly in its smaller size, narrower 

 rostrum, shorter broader interorbital region, narrower antorbital fora- 

 men, shorter nasals, and smaller audital bull^. Antorbital foramen 



narrower than in D. incomptus^ the 

 distance from its upper posterior 

 margin to the elevation on side of 

 rostrum marking root of incisor 

 relatively much less. Plate form- 

 ing outer wall of foramen relatively 

 wider than in D. incomptjis^ its an- 

 terior border concave below, ab- 

 ruptly convex above, but this con- 

 vexity never forming a pointed hook 

 as in the only specimen of Z). in- 

 comptiis at hand. Posterior extrem- 

 ity of nasals in line with center of 

 lachrymals, thus falling short of tips 

 of nasal branches of premaxillaries 

 by about 1.5 mm. In D. i7ico}?iptus 

 the nasals extend back to extrem- 

 ity of premaxillaries. Bony palate 

 very narrow, its width about equal to that of first upper molar. It is 

 traversed by two deep longitudinal grooves. Pterygoids straight, 

 slightly convergent posteriorly. Audital bulla2 relatively smaller and 

 more globular than \\\'D. mconiptus. Mandible less robust than that 

 of D. incoitiptus^ the coronoid process shorter (rising scarcely above 

 tip of articular process) and articular process much narrower. 



Teeth. — The teeth are exactly as in D. incomptus^ except that all 

 are distinctly less robust. Anterior face of incisors paler orange than 

 in D. inco7)2pt7is. 



Measurements. — External measurements of type : total length 302 ; 

 tail vertebric 151; hind foot 35 (32); ear from meatus 16.5; ear 

 from crown 13; width of ear 17. Average of four specimens from 

 the type locality: total length 306.5 (302-316); tail vertebrae 153 

 (151-156); hind foot 34 (33-35); hind foot without claw 30.4 

 (29-32). 



Cranial measurements of type: greatest length 35 (37);' basal 

 length 32 (34) ; basilar length 30 (32) ; palatal length 16. S (18.4) ; 

 palatal width between anterior molars 2.2 (2.4) ; diastema 10 (11. 4) ; 



' Measurements in parentheses are those of au adult D. iticompiwi from Port 

 Natal (topotype of D. gticinzii). 



