576 Mr. O. Thomas on 



LI. — Notes on Bats of the Genus Coleura. 

 By Oldfield Thomas. 



(Published by permission of the Trustees of the British Museum.) 



A STUDY of the Britisli Museum collection of the genus 

 Coleura, amounting to nearly sixty specimens from more than 

 a dozen localities, shows that on the mainland of Africa there 

 are two species: a north-eastern, inhabiting Suakin, Aden, 

 Somaliland, and the Upper Nile ; and a southern, which 

 ranges from the Congo to the Zambezi. The former is sepa- 

 rable into two colour-races. 



Then in the Seychelles there are two forms, botii distin- 

 guished from those on the mainland by their proportionally 

 lonirer wings. 



The genus mav thus be arranged as follows : — 



A. Wings shorter. Forearm not or little more 



than three times as long as the skull- 

 length *. 



a. Larger. Forearm 49-52 mm. ; skull 16'0 



and upwards ; maxillary tooth-row 7'2 



and upwards. (Ubangui, Angola, Tette.) 1. C. afia, Pet. 



b. Smaller. Forearm 45-48 mm. ; skull less 



than 16; maxillary tooth-row 6'7-7'l . 2. C. gallavum, sp. n. 

 a'. Hairs nearly vmicolor, wood-brown. 



(Suakin, Aden, Somali.) ^a. C. g. gallanim. 



b'. Hairs bicolor, sepia terminally, white 



basally. (Upper Nile.) 2b. C. g. nilosa, suhsp. n. 



B. Wings longer. Forearm more than 3^ times 



skull-length, 52 mm. and upwards. 



a. Larger. Forearm 55-57 mm. ; skull 15'2 ; 



maxillary tooth-row 7*0. (Seychelles, 



probably Mahe Island.) 3. C. seychellensis. Pet. 



b. Smaller. Forearm 52-54 mm. ; skull 



14-4-14-7 ; tooth-row G'5-6-7. (Sil- 

 houette Island, Seychelles.) 4. C. silhouettes, sp. n. 



Tt may be noted that the Seychelles species have usually a 

 median septal lidge in the basial pit, and the mainland species 

 not, but there are a great many individual exceptions to this 

 rule. The ridge is always more strongl_y marked in young 

 specimens than in old ones. 



1 fail to find any specific value in the characters used by 



* From condyle to front of canine. 



