(193) 



NEW OK LITTLE-KNOWN BATS 



21 



Rh. empusa, from Nyasaland; sella practically without con- 

 striction; ears somewhat shorter; horse-shoe very hroad; 



Rh. andreinii, from Gallaland and Erythrea; sella and ears 

 as in empusa, but horse-shoe somewhat narrower; 



Rh. blasii, from the Eastern Mediterranean countries , exclusive 

 of Egypt; sella abruptly constricted at middle; ears somewhat 

 longer; horse-shoe narrow; dentition (position of p 3 ) perhaps slightly 

 more advanced. 



The above linear (and therefore artificial) arrangement of the 

 three species, viz. (1) empusa, (2) andreinii, (3) blasii, might 

 suggest that Rh. blasii marks the highest stage in the chain of 

 evolution. So far as the dentition is concerned, it may be so, 

 provided the very small difference in the position of p a , as com- 

 pared with the two former species, is sufficiently constant to 

 warrant any safe conclusion (judging from other species of Rhi- 

 nolophus I have some doubt in this respect). But the constriction 

 at the middle of the sella, so pronounced in Rh. blasii, is deci- 

 dedly a primitive feature; we can follow it down to the most 

 primitive species of the Rh. lepidus group, and so persistent is 

 the character that we find it still preserved , though much less 

 conspicuous, in so aberrant a species as Rh. midas ('), from the 

 coast of the Persian Gulf, which also is an offshoot from the 

 lepidus group, and which leads to the well-known Palseartic 

 Rh. hipposiderus. 



The history of the Rh. empusa type, as far as it can be 

 read in the few fragments left to us, would seem to be as follows: 

 — It has originated from an Oriental bat allied to the now 

 existing Rh. subbadius, but with a deltoid sella, abruptly con- 

 stricted at the middle, and a more advanced wing-structure. From 

 South Asia tins bat spread in two directions: southwestwards to 

 Africa, westwards over S. W. Asia and the Eastern Mediterranean 

 countries. The southwestern branch , isolated by the breaking up 

 of the formerly more extensive land-connection between Asia and 

 Africa, lost, almost completely, the constriction of the sella, and 

 became differentiated into two very slightly differing species (or 

 races), a southern (Rh. empusa) and a northern (Rh. andreinii). 

 The western branch preserved the constriction of the sella (Rh. 

 blasii). 



(!) Proc. Zool. Soc. London 1905, II. p. 13S. 



