i'Ti:uAi,opi;\' AXCEP.'. 487 



leaTiinj;;s in curtain siiecics oi I'ieroitim, e.g. mehiiiopc>(;o)i, pajmaam;, 

 neokiiemicns, and molossinus), and the broadly rounded oars (as in 

 I't. liviiu/sloiiei) ; in all other respects I'teraluj^H.f is externally 

 closely similar to I'tcvopns psd'iphon. 



Dijfereniiaiion ofsjiccies. — The two known species rej)rescnt two 

 staf^es of specialization of the denl.ition. Ft. aureps (W. iSolonion 

 Is.) possesses all the essential dental characters of J't. airata (E. 

 kSolomou Is.), some of these fully as hi>>-hly developed as in the 

 eastern species (enlargeineut of ii])per incisors, outer lower incisors, 

 and Pp secondary cusp of upper canines), others decidedly less 

 developed (anterior basal ledge of upper molariform teeth not 

 extending on inner face of crown, less pronounced splitting of outer 

 cusp of Pj and m,), but at the same time it has preserved more of 

 the Pteropine shape of the cheek-teetli (inner cusps of upper cheek- 

 teeth more ridge-like, not conical, less excessive shortening of 

 xi])per and lower check-teeth). So far as the two latter categories 

 of characters are concerned, Pt. anceps therefore shows one of the 

 stages through which the still more highly specialized Pt. atrnta 

 must, in all ])robability, have passed. In the length and dis- 

 tribution of the fur Pt. anceps is nearer Pteropus piiclaphon i\iAn 

 is Pt. atrata, and the ear-couch has retained some trace of a 

 blunt tip. 



Key to the Species. 



a. Anterior basal ledge of p' not extending on 



inner side of tooth ; fur of back about 

 20 mm. ; tibia and metatarsus densely 

 clothed above; belly drab. (Bougainville) 1. Pt. anceps, p. 437. 



b. Anterior basal ledge of p* extending on inner 



side of tooth; fur of back 1:2-14 nun.; 

 metatarsus and distal fourth of tibia uaked ; 

 uniform blackish or seal-brown above and 

 beneath. (Guadalcanar) 2. Pt. (ifrala, ^. 439. 



1. Pteralopex anceps, K. And. 



Pteralopex anceps, K. Andersen, Ami, ^- Mat/. N. H. (8) iii. p. iit)6 

 (1 March, 190a : Bougainville). 



Dioipiosi^. — Dentition less specialized than in Ft. atrata ; ears 

 broadly rounded off above, but with a distinct trace of a blunt tip; 

 fur much longer than in atrata, uppersido of tibia and metatarsus 

 densely clothed, underparis conspicuously paler. Kize as the allied 

 species. Hab. Bougainville. 



Teeth (tig. 22, A, B, C). — p' more Pteropine in shape and struc- 

 ture than con-esponding tooth of Pt. atrata ; about one-tifth longer 

 than broad (actual measurements, anteroposterior diameter of 

 crown 5-8 mm., ti'ansveree diameter 4-8); anterior basal ledge 

 narrow, not extending on inner .side of tooth round base of inner 

 main cusp ; posterior ledge less heavy, particularly postero- 

 intci-nally, and not extending on inner side of tooth ; inner main 



