﻿364 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 102 



Description. — Upper parts from between Ochraceous-Orange and 

 Ochraceous-Tawny to deep slate gray; belly yellowish to light slate 

 gray. Color on body nowhere pure ; in light phase strongly suffused 

 with black-tipped hairs ; in dark phase uniformly slaty. Hands, feet 

 and tail of both color phases as belly color. Tail equal to head and 

 body in length, strongly annulated and with small bristlelike hairs. 

 Pelage coarse but becoming spinose between the ears and spines increas- 

 ing in size and number over the rump. Ears large, rounded, and but 

 sparsely covered with fine yellowish hairs. 



Measurements. — Averages and extremes of two males and six fe- 

 males from Alexandria, Behera Province, Egypt, were, respectively : 

 Total length 209.5 (198-221), 218.6 (208-225) ; length of tail 113.6 

 (108-121), 106.6 (97-112) ; length of hind foot 19 (18-20), 18 (18) ; 

 length of ear from notch 18.5 (17-20), 18 (17-20) ; greatest length 

 of skull 28.05 (27.0-29.1), 28.28 (27.9-28.9); condylobasal length 

 23.85 (22.7-25.0), 24.0 (23.^24.8) ; length of palate 14.55 (13.5-15.6), 

 14.32 (13.7-15.0) ; alveolar length of upper molar series 4.3 (4.2-4.4), 

 4.4 (4.4); length of palatal foramina 6.3 (6.2-6.4), 6.2 (5.8-6.6); 

 least interorbital width 4.8 (4.8), 4.7 (4.6-4.8) ; length of nasals 10.3 

 (9.9-10.7), 10.6 (10.2-11.1). 



Remar'ks. — These small spiny mice have, at various times, been 

 designated by various specific or subspecific names. Most of these 

 names have, apparently, been based on differences in color. From 

 the specimens now at hand, it appears that the only name strictly 

 applicable is Aconiys cahirinus. E. Geoffroy St.-Hilaire evidently 

 had before him a specimen of the light-colored phase when he de- 

 scribed this animal, and subsequent authors must have had repre- 

 sentatives of the other more melanistic types. In all, the two basic 

 types of pelage color are light above and light below and dark above 

 and dark below. From these two phases all possible gradations can 

 be demonstrated by specimens from Abassia Fever Hospital, in Cario, 

 or from Alexandria. 



From ail appearances this peculiarity of color is nothing more than 

 the expression of melanism. In many ways these small mice recall 

 the variation of pelage found in Rattus rattus and considered by many 

 to be subspecies. 



Family DIPODIDAE 



JACULUS JACULUS JACULUS (Linnaeus) 



Mu% jacuUis Linnaeus, Systema naturae, ed. 10, p. 63, 1758 (type locality given 

 by Linnaeus as "In Arabia, Calmukia," emended by Allen (1939, p. 423) as 

 Pyramids of Giza). 



Specimens examined. — ^Twenty-two. Giza Province: Abu Rau- 

 wash, 5 (MVZ) ; Suez Road, 5 miles east of Heliopolis, 4 ; 1 mile north- 



