25G Bats of the Rliinoloplins pliilipplncnsls Group. 



One of these modifications of the skvill, in the trifoliatus 

 section, is very instructive. When, as is the case in other 

 Rhino/ophi beyond a certain low level of development, the 

 temporal muscle increases in size, the sagittal crest creeps 

 more forn'ctrds (as in many other Mammalia), reducing the 

 length of the supraorbital crests, consequently also the 

 length of the postnasal depression, which is bordered laterally 

 by the supraorbital crests. In the trifu/iatus-ty\-)e the shape 

 and size of the nose-leaves seem to require a rather long and 

 very deep postnasal depression ; therefore the temporal 

 muscle, when growing larger, cannot very well push the 

 sagittal crest much iarther fo7'ica7'ds ; instead of that it pushes 

 the crest upicards, making it unusually high in front. This 

 accounts for the peculiar shape of the sagittal crest, as 

 figured, on p. 245 (fig. 2) . 



The subjoined diagram gives a view of the probable 

 inter-relations of the species : — 



permger. 



geminus. 



luctus. 



Imwsus. 



Maclaudi. 



raitratm. 



X 



philippinensis. 



trifc 



Beddomei. 



solitarius. 



iatus: 



sedulus. 



