PIPISTRELLUS SUBULIDENS sp. nov.
Type.—Adult female (in alcohol) No. 104758 U. S. National Museum. Collected on Sirhassen Island, South Natunas, June 3, 1900.
Characters.—Similar to Pipistrellus pipistrellus (Schreber) in size, color and external form, but skull with broader rostrum, and inner upper incisor without supplemental cusp.
Skull.—The skull is of the same size as that of Pipistrellus pipistrellus, but the braincase is narrower and more elongate, and the rostrum is very markedly shorter and broader. The great breadth of the anterior portion of the skull involves also the palate and interpterygoid space, both of which are noticeably wider than in Pipistrellus pipistrellus. Audital bullæ slightly smaller than in the European species.
Teeth.—The teeth are essentially as in Pipistrellus pipistrellus, except that the inner upper incisor lacks the small supplemental cusp. Mandibular teeth wider than those of P. pipistrellus.
Measurements.—External measurements of type: total length 76; head and body 41; tail 33; tibia 14; foot 6; calcar 10; forearm 32.4; thumb 6; second digit 30; third digit 60; fourth digit 53; fifth digit 43; ear from meatus 11; ear from crown 9; width of ear 9.6; tragus (measured in front) 4.
Cranial measurements of type: greatest length 12.4 (12);[26] basal length 11.8 (11.6); basilar length 9 (9); zygomatic breadth 8.4 (8); least interorbital breadth 3.2 (3.2); greatest length of braincase 8 (7.6); greatest breadth of braincase above roots of zygomata 6.6 (6.6); mandible 8.8 (8.4); maxillary toothrow (exclusive of incisors) 4.2 (4.2); mandibular toothrow (exclusive of incisors) 4.8 (4.8).
Specimens examined.—Six (in alcohol), all from the type locality.
Remarks.—I am unable to identify this bat with any described species. Externally it is practically identical with Pipistrellus pipistrellus except that the color, so far as can be judged from specimens preserved in alcohol, is more blackish. Internally it is readily distinguished by the characters of the skull and teeth. From Pipistrellus abramus it differs externally in smaller size, narrower ears, and in the absence of any unusual development of the penis. The incisors differ from those of P. abramus in the same manner as from those of P. pipistrellus.