1917.] 



Lang and Chapin, Field Notes on African Chiroptera. 



511 



7. Casinycteris argynnis •( Thomas). 



Only a single specimen of this rare fruit-bat was previously known from 

 the Kamerun and our record from Medje in the Ituri shifts the limit of 

 its range at once 900 miles eastward. Its queer dentition and other struc- 

 tural characters make it a bat of great interest and any positive clue as to its 

 food and habits would be an important contribution. 



Casinycteris argynnis is a rather small, practically tailless fruit-bat of 

 about 3.5 inches (92 mm.) in length. The fine hair on the upper side has 

 the peculiarity of being dark brown at the base, lighter in the center and 

 brown again at the tip. The crown and nape are somewhat lighter. The 

 grayish-white sides of the neck and throat fuse with a patch of the same 

 color that runs down the short-haired abdomen between the gray-brown 

 sides. A white spot behind the nose, where the hair starts to become longer, 

 and one at the posterior corner of the eyes, and a white border on the upper 

 lips are also characteristic of this bat. It is further distinguished by the 

 fact that the wing membrane joins with the phalanges of the first and not 

 with those of the second toe as in all the other fruit-bats we collected, ex- 

 cept Eidolon hehum. 



In the fresh specimens the rather flat nose is a dirty pink, but the skin 

 visible underneath the hair is pale yellowish. The ears have only faint 

 white tufts at their base and are, like the wing membranes, yellowish brown; 

 the phalangeal joints however are much lighter. The eyelids are straw- 

 colored but the round pupil was so large that we almost overlooked the 

 yellowish-brown iris. 



Its queer premolars and molars, the enormous spreading of the zygomatic 

 arches that goes hand in hand with a strong and broadened ascending ramus 

 would indicate a crushing rather than a cutting dentition. These char- 

 acters, together with the short bony palate and the curiously developed 

 palatal ridges, seem indicative of a diet very different from that of ordinary 

 fruit-bats, especially as the shortness of its tooth-row also suggests features 

 typical of insectivorous bats. Unfortunately its stomach was empty, though 

 we found one fcetus (April) in dissecting. 



This bat was hanging alone in the dense foliage of a bush only ten feet 

 from the ground at the edge of a native village near Medje, and was the 

 only specimen we saw. 



8. Myonycteris wroughtoni Andersen. 



An inconspicuous and very small fruit-bat, it attains only 5 inches (130 

 mm.) in length, of which the tail absorbs half an inch. The four specimens 



