NOTES ON THE GENERA OF VESPERTILIONIDiE. 

 By Harrison Allkn, M. I). 



At tlie, coiicliisioii of a stmly of this family 1 venture to place on 

 record my views I'espectini,^ tlie position of the genera Antrozous, 

 (Joryiiorhinus, Synotiis, Xoctiilinia, and Kerivoula. 



Antrozom. — Antrozous is a composite genus. It is not specially re- 

 lated to Corynorhinus and Plecotus. In the incomplete tympanic bone, 

 in the absence of the palatal plate to the premaxilla, in the markings 

 on the fourth digital interspace, in the shape and relation of the ulna, 

 in tlie i)ossession of a tubercle on the palmar surface of the trapezium, 

 in the details of the molars, in the arrangement of the nasal scrolls, 

 and in the deflection of the cartilage of the fourth digit toward the 

 thumb, Antrozous is in alliance with Vespertilio. It is distinguished 

 therefrom by the absence of the accessory cartilage to the fifth digit. 

 Aflinity with Corynorhinus is suggested by the shape of the muzzle- 

 glands. Antrozous resembles Atalapha in the shapes of the last molars 

 as well as in the proportions of the hypoconid, but in the presence of 

 four incisors in the lower jaw,* in the free lower lip, in the head not 

 being in axis with the body, in tlie maiial formula, in the disposition 

 for the nostril to bear a vertical internarial ridge and the upper border 

 of the muzzle a constant transverse outgrowth, in the presence of a 

 hem of membrane on the pollical side of the second metacarpal bone, 

 recalls the Phyllostomidse. 



Corynorhinus. — This genus is in close relation to Eudcrma and Pleco- 

 tus, so the term Plecoti adopted by Dobson is a useful one to be em- 

 ployed in this restricted sense for the genera above named. 1 would 

 exclude from the group Antrozous and Synotus. Nyctophilis and 

 Otonycteris I have not studied. Corynorhinus differs from Antrozous 

 in the greater development of the hypocone in the upper jaw and its 

 equivalent in the lower jaw. The points of the cusps are more pro- 

 duced than in the genus last named. The thumb is semiflexed (thus 

 denotive of free motion in the carpometacarpal joint), the callosity is 

 rudimentary. The palmar aspects of the manal digits are well defined 

 at the proximal ends, being thus without the radiated raised folds of the 

 skin seen elsewhere in the family. The terminal cartilages of the digits 



* lu the restriction of the lower incisors to four in a family where the dominant 

 number is six it is of interest to note that in Xycti7iomus brasiliensis the tliird in- 

 cisor on each side is rudimeutal or may be hjst, thus reducing the number from sis 



to tour. 



29 

 Prooee^iuga JTationi*! Mvtseuiu, Vol. XVI— Np. 880. 



