174 PROCEEDINGS OP THE ACADEMY OP 



beyond the incomplete infra-orbital ridges, to which the infra-orbital fora- 

 mina are nearly contiguous. Zygomatic arch expanded at posterior third. 

 Molars 5. Cochlea? not visible. Internal basal lobe of ear rounded, thicken- 

 ed, gradually losing its distinctness along the marked fold at inner border. 

 Inter-auricular membrane rudimentary ; external basal lobe terminating on 

 a line with the angle of the mouth ; it possesses a manifest lobe on the internal 

 surface. Antitragus scarcely perceptible. Tragus pointed gradually, ex- 

 ternal basal lobe conspicuously cupped. Nose with two lateral hairy con- 

 Terging excrescences nostrils wider than long, subtriangular. No rounded 

 swelling at base of foot. Vertebrae of tail, <.* 



C. MACROTIS.f 



Head half the length of body. Upper lips tumid, on sides of face rather 

 thickly set with pendant hairs. Excrescences on a line with the lateral 

 border of nostrils sparsely haired ; tuberosities at base flattened, well defined 

 posteriorly. Nostrils terminal, of an irregular triangular shape, the apices 

 pointing inward ; exterior lateral angle acute, borders not everted ; mental 

 space narrow, crescentric. Ears, length of body, with internal fold one-fifth 

 width of auricle, sparsely haired at internal border, tips turned slightly out- 

 wards outer half of auricle marked with irregular transverse lines ; the inner 

 lip to external basal lobe convex, nearly as high as long. Antitragus simple, 

 linear. Tragus nearly half the height of auricle, interior border' thickish 

 and marked with a few hairs, tip rather blunt; exterior basal lobe longer 

 than wide inner and outer borders deflected upwards. Outer end of the free 

 edo-e of the sigmoid internal lobe thickened. Fur long and silky, that of the 

 back of a blackish hue at base, verging to an obscure fawn or brown at tip. 

 The hair is, therefore, indistinctly bi-colored. The extent of the tip colora- 

 tion varies but in all specimens that of the color of the base predominates. 

 The hair of the belly is blackish at root, in some specTmens slightly plumbe- 

 ous. Tips grayish, running to white toward the pubis. 



Compare Plecotug {P. auriius.) Skul! # not depressed at vertex; supra-occipital space well 

 defined but little inflated; frontal bone crested. .Nasal bones narrow, depressed, no median fossa. 

 Orbital process produced, bounded anteriorly by the infra-orbital ridge, which is sharply defined, 

 complete, and protects the infra-orbital foramen immediately in front. Zygomatic arch expanded 

 at middle third. Molars ; cochleae not visible. Internal, basal lobe of ear obscure; a thin 

 papery fold terminating the internal border, and rung thence upwards and inwards, terminates 

 in a prominent, thickish lobe, forming the outer boundary of the large inter-auricular membrane. 

 Antitragus salient, convex, external basal lobe simple. Tragus bread, points sharply; external 

 basal lobe developed, incurred upon itself. Nose simple nostrils longer than wide, with tumid 

 inner, walls. Base of foot with small rounded spelling. Joints of tail, 8. 



Vespertilio. {V. subulatus.) Skull not depressed at vertex; supra-occipital region greatly 

 swollen; par-occipital process trenchant, matly as long as condyles; nasal bones narrow, convex, 

 higher than orbital process, and tape ing from above downwards. Orbital process slight, swollen, 

 not involving side ot face ; infra-orbital foramen at posterior fourth of orbito-nasal space. Zygo- 

 matic arch convex, not expanded, becoming more slender posteriorly, depressed in middle. 

 Cochleae visible. Molars . Internal basal lobe of ear simple, acute, inner border of auricle 



simple. No swelling at. base of foot. Vertebrae of tail, 9. 



BarbasUlius. (B. communis.) Skull scarcely depressed at parietal suture. Nasal bones flat, 

 depressed below the level of the orbital process; internal process produced inferiorly at anterior 

 nares. Infraorbital ridge rudimentary, foramen midway between orbit and anterior nares. Zygo- 

 matic arch straight, and of uniform tenuity. Molars A. Cochleae visible posteriorly. Internal 

 basal lobe of ear scarcely perceptible, not joining the small inter-auricular membrane; internal 

 border of ear not folded backwards, but erect; external border sinuate; external basal lobe 

 simple, terminating above the angle ot the mouth. Antitragus sharp, well defined, convex. 

 Tragus points gradually, external border obscurely bi-eiuarginated ; basal lobe simple, inferior 

 border alone curved, to form a minute wart. Nose simple, truncate; nostrils irregular, inner 

 border produced laterally* not tumid. No rounded swelling at base of foot. Joints of tail 9. 

 (This genus has remote affinities with Nycteris aud Megaderma.)* 



t (Mon. N. A. Bats, loc. cit.) 



Histiotus, Gervais, (Castelnau's L' Amerique du sud Mam. 1855, p. 7" , pi. xiii. f. 6) apparently 

 belongs to this group. 1 have not had an opportunity of examining it. 



[Aug. 



