384 PTERorrs XEoHiiiF.nxicrs grott. 



an immature male, was acquired by the British Museum and 

 described by Gray, in 1870 (/. s. c), as Pt. mysolensis var. ceramensis. 

 Dobson (Cat. Chir. B. M. 1878) recognized Ft. ocularis as a distinct 

 species allied to Pi. conspicillatns ; but Gray's type of Pt. mysolensis 

 var. ceramensis, although in reality indistinguishable from, and 

 even a topotype of, Pt. ocularis, he referred to Pt. alecto (specimen g). 

 By Matschie (I. s. c. 1 899) Pt. ocularis was put down as doubtfully 

 distinct from Pt. htj [lomdanus (subgenus Spectrum, whereas Pt. 

 chri/sauc7ien and Pt. conspicillatas were placed in the subgenus 

 Pteropus), a conclusion that apparently was based rather more on 

 geographical considerations than on the actual characters of the 

 species, the true affinities of which, as proved by sliull, dentition, 

 and all external characters, are with Pt. chry.muchen and con- 

 spicillatus, not with Pt. hypomelanus. 



a. c? imm. sk. ; skull. Ceram. Dr. A. E. Wallace [C.]. 61.12.11.2. 

 {Type of Pt. mysolensis var. ceramensis, (jna,y.) 



0. Thb Pteropus neohibernicus group. 



Species. — Pt. papuanus, neohibernicus. 



Range. — New Guinea, Bismarck Archipelago. 



General characters. — Skull typical Pteropine. Cheek-teeth with- 

 out posterior basal ledges. Palate-ridges 5 + 8-1-3. Ears short, 

 somewhat attenuated above; interfemoral scai'cely developed in 

 centre; fur of back very short, adpressed, iu adult individuals 

 restricted to a narrow spinal tract. Colour varying. Males 

 without glandular neck-tufts. Size very large (forearm about 

 189-200 mm.). 



Specific differentiation. — The two species, the one inhabiting New 

 Guinea {Pt. papuanus), the other the Bismarck Archipelago {Pt. 

 neohibernicus), are very closely related, differing apjiarently only in 

 the darker or paler colour of the back. 



Affinities of group. — The group differs from all other groups of 

 the genus by the combination of these two characters : cheek- 

 teeth without posterior basal ledges, furred area of back confined 

 to spinal tract. The only other species showing this latter 

 character is Pt. melanopoyon, which however differs widely in 

 dentition. 



There can be little doubt t/hat the Pt. vampyrus, alecto, chrys- 

 auchen, and neohibernicus groups represent four branches of one 

 type of the genus, viz., an Indo-Malayan (vampyrus), a Celebeau 

 (alecto) extending also to the Lesser Sunda Islands and Australia, 

 a Moluccan {chrysauchen) extending to New Guinea and Australia, 

 and a New Giiinean branch (neohibernicus) extending to the 

 Bismarck Archipelago. The four groups are remarkably alike iu 

 skull and dentition; in all the fur is very short and closely ad- 

 pressed on back. The ears are nearly of the hypom^lanvs style in the 

 alecto, chrysauchen, and nejhiliernicus ^xon^s, long and pointed only 

 iu the vampyrus group. The interfemoral is short iu the centre 

 ill the chrysauchen and neohibernicus, conspicuously deeper in the 



