CHEIROMELES TORQUATUS. 



tion of the genus. I shall add a few remarks on its immediate relations. It has 

 been stated as a query in the notice of its affinities, whether Cheiromeles, Nycti- 

 nomus, Molossus, Dysopes, and Myopteris should not form a separate subdivision 

 in the family of VespertilionidEe. As far as regards their front teeth, the resem- 

 blance between all these is strong; it is as follows : — Cheiromeles -|, Molossus -|, 

 Myopteris |-, Dysopes |-, and Nyctinomus -|. These genera have likewise a 

 striking aflfinity in the size and organization of the ears, in the nakedness of the 

 nose, in the great expansion of the wing, and in the structure of the tail, enveloped 

 at the base in the interfemoral membrane, and detached at the extremity. Among 

 these, on first view, Cheiromeles appears to have the greatest resemblance to Mo- 

 lossus ; but the comparisons which I have instituted, shew that it is still nearer to 

 Nyctinomus; therefore, without entering into a separate analysis of the genera 

 enumerated, and their affinity individually to Cheiromeles, I shall mention in detail 

 only those particulars in which it agrees with Nyctinomus, as they appear in the 

 form of the skull, in the teeth, in the structure of the ears, in the nose, in the 

 anterior extremities, in the interfemoral membrane, in the tail, and in the brush- 

 like appendage of the thumb and fingers. First: — The form of the skull in Cheiro- 

 meles and in Nyctinomus is almost precisely the same ; to shew this, a comparison 

 of the details which are given in our Plate, with those contained in the Illustrations 

 to the Vth Number of these Researches, is sufficient. Secondly : — The front and 

 canine teeth in both these genera have so nearly the same character, that the descrip- 

 tion of them in one may, with a very small modification, be applied to the other. 

 The grinders likewise are constructed exactly on the same plan ; but their analogy 

 shews itself strongest in the lower interior ridge of the upper grinders, which is 

 emarginate, and supports two points, of which the anterior is largest. Thirdly : — 

 regarding the ears it may be remarked, that in Nyctinomus the auricle is larger, 

 and has a more anterior situation ; but in the great extent of this organ interiorly, 

 in the form of the enlarged tragus, and in the covering which the auricle is calcu- 

 lated to afford to the eye, both these genera agree. Fourthly : — The nasal tubes and 

 the end of the rostrum are similar in Nyctinomus and in Cheiromeles : both genera 

 are distinguished by numerous conical spinous glands situated on the rostrum ; but 

 in Cheiromeles these are separated and distributed in various fascicles, while in Nyc- 

 tinomus they are collected near to one point. Fifthly: — The agreement which 

 exists between Cheiromeles and Nyctinomus in the anterior extremities, shews 

 itself not so much in the size and form of the membrane, as in the great length and 

 delicacy of the phalanges of the fingers. Sixthly : — The structure of the interfemoral 

 membrane, and the muscular fibres with which it is provided, in both these genera 



