448 PHTLtOSTOMIDJE. 



backwards ; the nasal apertures circular, close together, opening on 

 this obliquely directed surface ; lower lip much expanded and folded 

 outwards, with numerous small rounded papiUas in front ; chin with 

 a horizontal cutaneous expansion. 



Wing-membrane from the proximal extremity of the calcaueum 

 and from the tibia ; interfemoral membrane large, with long cal- 

 canea ; tail perforating the membrane, and appearing upon its upper 

 surface. 



Dentition. Inc. -j, c. j— j, pm. g^, m. g^. 



The upper middle incisors larger than the outer incisors, with 

 broad notched edges ; the lower incisors triangular in cross section, 

 the base outwards ; second lower premolar minute, half internal. 



Mange. Tropical parts of the Neotropical liegion. 



The species of this genus are insectivorous ; the stomachs of 

 individuals examined by Mr. Osburn and by the writer were 

 invariably found to contain remains of insects. 



All the species are very closely allied to one another, agreeing 

 together remarkably in the form of the muzzle and of the cutaneous 

 chin appendages, in the peculiarly attenuated ears, in the general 

 structure of the body, and, especially, in dentition. In one species 

 (Ch. davyi) the wing-membrane, instead of arising from the sides of 

 the body as in all the other species, is connected to the centre line of 

 the back by a narrow ligament only, and the back of the animal 

 behind the shoulders is naked. On this account this species has 

 been made the type of a genus {Pteronotus, Gray) ; but that genus 

 cannot stand, neither can the character on which it is founded be 

 considered sufiicient to warrant the formation of a distinct sub- 

 genus, for Ch. davyi differs in none other important respect from 

 the other species of the genus, and the variability of the point of 

 attachment of the wing-membrane is quite as well marked in other 

 genera of Chiroptera. 



Synopsis of the Species. 



I. Wings from the sides of the hairy back. . (Subgen. Chilonycteris.) 

 a. Lower third of the inner margin of the 

 ear-conch thickened and separated by a 

 right-angled notch from the upper two 

 thirds. 

 a'. A small tooth-like projection from the 

 upper margin of each nostril; outer 

 margin of the ear-conch abruptly con- 

 vex at the commencement of its lower 

 two thirds, forming an acute-angled 



notch ; forearm l"-65 1. Ch. ftiackayit, p. 449. 



b'. No tooth-like projection from the upper 

 margin of each nostril. 

 a". Outer margin of the ear-conch ab- 

 ruptly convex at the commencement 

 of its lower two thirds, forming a 

 right-angled notch ; forearm 1"'8 , . 2. Ch. per sonata ^ p. 451, 



