1917.] 



Allen, Lang and Chapin, Bats from the Belgian Congo. 



459 



furred. Pad at the base of the thumb large. (For illustration of wing see Part II, 

 p. 550, by Lang and Chapin.) 



Collectors' measurements of type: Total length, 102 mm.; head and body, 68; 

 tail, 31; foot, 10; ear, 21. Additional measurements from the dry skin: Forearm, 

 45.7; third metacarpal, 45.4; tibia, 38; foot, 10.5; ear, length of outer border, 25.7; 

 height from crown, 19.3. 



Collectors' measurements, type and 23 adult topotypes (4 males, 20 females) : 

 Total length, 100 (93-105); head and body, 67.8 (62-73); tail, 33.1 (29-36); foot, 

 11.2 (10-13); ear, 20.2 (19-22). Forearm, from the skins (same specimens), 44.6 

 (42-46). 



Skull rather deep and narrow; median and lambdoid crests weakly developed, 

 especially the former; preorbital ridge conspicuous; premaxillae fully ossified, enclos- 

 ing a pair of small palatal foramina. Upper incisors small, slightly separated at 

 base with their tips nearly or actually in contact (in different specimens); lower 

 incisors §E§, small, all bifid, the inner more deeply so than the outer with the inner 

 lobe the larger; outer incisors partly posterior to the middle pair. Upper canines 

 with a broad, deep longitudinal groove and small cingulum without cusps; lower 

 canines without distinctive features. First upper premolar minute, closely crowded , 

 between the adjoining teeth and wholly separating them; second upper premolar 

 large, more than half the size of m 1 ; first lower premolar a little smaller than the 

 second. 



Skull (type), total length, 18.7; condylobasal length, 16.6; zygomatic breadth, 

 11; mastoid breadth, 10.1; interorbital breadth, 4.1; maxillar breadth, 7.9; breadth 

 of braincase, 9.3; upper toothrow (with canine), 6.4; length of mandible, 12.2; 

 angle to condyle, 2.5; depth at coronoid, 3; lower toothrow, 7. 



Skull, type and 22 topotypes, total length, 18.5 (17.8-19.4); zygomatic breadth, 

 11 (10.5-11.4). 



Represented by 27 specimens (24 skins with skulls, 3 alcoholic), all taken at 

 Medje, September 8, 1910. 



The series is exceedingly uniform in both coloration and measurements. 

 The pelage of the dorsal surface is without light tips to the hairs, and the 

 pelage of the ventral surface is nearly so, a few of the specimens, however, 

 having the extreme tips of the hairs pale buffy over the median area. 



Chcerephon russatus closely approaches C. demonstrator (Thomas) in 

 size and proportions, but the latter is somewhat larger, especially in cranial 

 measurements, the zygomatic breadth being about 2 mm. greater. The 

 upper canine and second upper premolar are said to be in contact in C. 

 demonstrator, with the minute first premolar in the outer angle between 

 them, while in russatus the small premolar is in the middle of the toothrow, 

 completely separating the canine from p 4 . The description of the colora- 

 tion of demonstrator also does not agree well with that of russatus, nor does 

 the indicated structure of the ears. The fleshy protuberance in front of the 

 ears seen in russatus is found also in other species, which in other respects 

 are widely different. It is said not to be present in demonstrator. In an 

 alcoholic male of russatus there is no indication of the pair of scent glands 



