100 Proceedings of the Biological Society of Washington. 



Pteropus arquatus, sp. nov. 



Type from Koelawi, Middle Celebes. No. 218,612, U. S. National 

 Museum; skin and skull of adult male (teeth slightly worn); collected 

 January 5, 1917, by H. C. Raven; original number, 3067. 



External characters. — A medium sized animal related to the members of 

 the alecto and conspicillatus groups (Andersen, p. 96); forearm 133-141 mm.; 

 ear essentially as in Pteropus alecto; general color both above and below a 

 variegated golden brown; a dark area extending from muzzle to eyes and 

 ears and across chin and throat; a faint whitish mark over eye; back 

 sharply contrasted dark auburn in young individuals, this area in adults 

 sprinkled to a varying degree with yellowish hairs which often become 

 dominant and in some instances almost completely obscure the brown. 



Skull and teeth. — The skull differs from that of Pteropus alecto (repre- 

 sented by a large series collected by Mr. Raven at Sigi, Middle Celebes), 

 which it approaches in size, in its broader, more robust general form 

 (zygomatic breadth in type 37 mm., greatest length 66.2; in an adult male 

 alecto with the same zygomatic breadth the greatest length is 71.6), and 

 especially in the reduced length of the rostrum (distance from anterior rim 

 of orbit to tip of nasal in the two specimens just mentioned 19.6 and 25.4 

 mm. respectively), a peculiarity which makes it closely resemble the much 

 smaller skull of Pteropus capistratus. Teeth resembling those of Pteropus 

 alecto and P. aterrimus but m' and mi not conspicuously different from the 

 preceding premolar, and m^ with essentially the same structure as m'. 



Measurements. — Type: Head and body, 230; tibia, 64; foot, 42 (34); 

 forearm, 138; thumb, 60; longest finger, 260; third metacarpal, 93; ear from 

 crown (dry), 26; greatest length of skull, 66.2; condylobasal length, 64.0; 

 zygomatic breadth, 37.0; interorbital constriction, 9.0; postorbital con- 

 striction, 7.2; breadth of braincase above zygomatic roots, 24.2; mandible, 

 52.2; maxillary toothrow, exclusive of incisors (alveoli), 24.8; crown of m* 

 5.0 X 3.6; maxillary toothrow exlusive of incisors (alveoli), 28.6. 



Specimens examined. — Twenty-nine, all from Middle Celebes: Koelawi, 



11; Sigi, 18. 



Cheiromeles parvidens, sp. nov. 



Type from Pinedapa, Middle Celebes. No. 219,350, U. S. National 

 Museum; skin and skull of adult female (teeth not worn); collected Febru- 

 ary 20, 1918, by H. C. Raven; original number 3547. 



Characters. — Like Cheiromeles torquatus but general size slightly less and 

 teeth disproportionately smaller. 



Measurements. — Type: Head and body, 123; tail, 59; tibia, 28.4; foot, 

 22; forearm, 72; thumb, 19; third finger, 170; third metacarpal, 74; greatest 

 length of skull, 30.0; condylobasal length, 27.2; zygomatic breadth, 20.0; 

 interorbital constriction, 8.2; lachrymal breadth, 12.2; breadth of braincase, 

 15.0; mandible, 21.6 (24.2);' maxillary toothrow exclusive of incisors 

 (alveoli), 10.0 (11.2); combined length of m' and m^ 5.8 (6.6); width of m« 

 at middle, 3.2 (3.6) mandibular toothrow (alveoli), 11.4 (12.8); combined 

 length of mi and m2, 5.8 (6.6). 



1 Measurements in parentheses are those of an adult female Cheiromelti toTduatuB from 

 Borneo (No. 102,463). 



