NYCTINOMUS TENUIS. 



of which the lengthened nasal tubes are bent and pressed to such a degree, that 

 the communication from without, between the nasal fossae, is suspended. The 

 transparent membrane of the anterior extremities is as in the genus Noctilio, 

 which the Nyctinomi also resemble by the hare-lip. The hind feet are covered with 

 hair, of such length as to extend beyond the claws. It is remarkable that this 

 circumstance should be placed necessarily in the number of the generic characters of 

 this small group : it is observed among the Nyctinomi alone, and it is found in all 

 of them. The tail presents a form which is as yet new : it is almost as long as in 

 the genus Vespertilio, but it has a portion only enveloped in the interfemoral 

 membrane. This membrane is smaller than in the last-mentioned genus, but it is 

 tliicker, and supported, or rather drawn inward, by strong muscular fibres. It forms 

 a sack by means of natural folds, in consequence of the membrane of the wings 

 passing over the carpus, to unite itself without interruption to the interfemoral 

 membrane. 



Mr. GeofFroy enumerates three species of Nyctinomi : the first was discovered 

 by himself in Egypt ; the second is described by Dr. Buchanan (Hamilton) in 

 the Vth Volume of the Transactions of the Linnean Society, with the name of 

 Vespertilio plicatus; the third was found by Commerson in Mauritius, and was 

 described fi-om his materials by Herman, in his Observationes Zoologies, page 19, 

 with the name of Vespertilio acetabulosus. The first is named by M. GeofFroy ,^ 

 Nyctinome d'Egypte ; the second, Nyctinome du Bengal ; and the tlrird Nyctinome 

 de Port-Louis. 



A fourth species of this genus, the Nyctinomus tenuis, was discovered by me in 

 Java ; and in the following description, the characters which it has in common 

 with the other Nyctinomi, and the peculiarities which characterize it as a species, 

 will be detailed. The ears are of excessive size, and in a great measure conceal 

 the head : theh form is irregularly oblong, and they are surrounded by a membra- 

 naceous margin, united on the crown of the head, from which they stretch forward 

 so as completely to cover the forehead. At the lower extremity of the auricle a 

 rounded obtuse lobe, formed as in several other genera of this order, by the 

 enlargement of the tragus, covers the meatus auditorius. The skuU is considerably 

 compressed. The eyes are extremely minute, almost concealed from view, and 

 covered by the lower fold of the membranaceous border of the ear. The upper lip 

 is very fleshy, marked with seven or eight large transverse folds, and passes forward 

 to unite itself with the nose, which is large, surrounded by a delicately crenated 

 margin, and deeply emarginate at the extremity. The nostrils are circular, obscure, 

 and placed at the extremity of the nose. The lips .and lateral parts of the face are 



