506 On Hipposiderus diadeiiia and its closest Allies. 



is tliat the Solomon Island and New Guinea forms are most 

 closely related to each other, likewise the Philippine and 

 the Cclehes-Borneo-Sumatra forms, whereas the Java-Timor 

 form is a trifle more aberrant from what we may well suppose 

 to be the " ancient style/^ 



In H. d. vk'ariM5 we found a certain tendency to reduction 

 of the lateral ridges on the front of the posterior leaf. In 

 H. Masoni, from Lower Burma, they have quite disappeared 

 (provided Dobsou's description of this bat is correct). 

 H. nicobarensis , in which the same is said to be the case, 

 Avould seem to be a pigmy form of this modification, 



H. lankadira is most closely related to H. diadema ; the 

 facial width is as in an average form of that species, but the 

 skull is much more heavily built, the teeth markedly larger, 

 and the shape of the posterior leaf a little aberrant ^. 



In Batchian (and neighbouring islands?) we find the 

 diadema type modified into the large-eared and big-faced 

 H. euotis, but still the teeth have retained their usual size. 

 This form seems to lead to the very large, big-faced, large- 

 toothed, large-eared, and exceedingly long-legged H. dinops, 

 from the Solomon Islands ■\. 



Thus the Solomon Islands, though being the extreme 

 eastern limit for the group dealt with in this paper, are 

 inhabited by two modifications of the same type of bat. 

 But it must be remembered that these two forms (//. d. 

 oceanitis and H. dinops) have been derived from two different 

 branches of the fundamental type, the former from the 

 " diadema" branch, the latter, probably, from the ''euotis" 

 branch, and that they therefore, very likely, have spread to 

 these far eastern islands at different times and by different 

 ways. 



* H. diadema hns been recorded from the Central Provinces of India 

 (Dobson, Mon. Asiat. Chir. (1876) p. :^00, nos. 293-296) ; I have seen no 

 specimens from the Indian Peninsula. — Dob^on also registers an adult 

 female, in tlie collection of the Calcutta Museum, from Darjeeling 

 {I.e. no. 292; see also J. Anderson, Cat. Maunn. Ind. Mus. Calcutta, 

 1881, p. 115). Is that a H. diadema (not a H. annir/er) ? 



t The Solomon Islands are indeed peculiarly fertile in the production 

 of giant species: Mus imperator, Mus rex, liana Gtip2)i/i, to which is now 

 added Hipposiderus dinoj)s. 



