772 NOTES ON THE VAMPIRE BAT— ALLEN. vol.xviii. 



wrist. The anterior, surfaces of tlie inferior extremities are covered 

 with woolly gray liair as far as the ankles. 



The face is nearly naked, but a conspicuous pencil of hair occupies 

 the space between the eye and the nose leaf. 



The description of the fur by Dobson is as follows: ''Fur above, 

 reddish brown; beneath, yellowish white, darker at the base of the 

 hairs.'' The inadequateness of this description when compared with 

 the above accouut is evident. In the National Museum specimens, the 

 base of the hair is everywhere Avhite. and the hair of the crown and 

 back of the neck is for the greater part of its length pure white. The 

 shades of brown are nowhere to be interpreted as reddish brown. 



The general scheme of fur distribution is of interest. As a whole, 

 the genus is more hirsute than Desmodus. The hairiness of the thumb 

 and back of the foot, and the extension of hair on the endopatagium, 

 are unusual characters. The appropriation of hair by the wing mem- 

 brane to the outer side of the leg is also unusual. In Artihens I have' 



noted how the skin in the 



^*i*wKteft^.^ region of the fibular side of 



^^v.V. .V ',^m^wr-r-r7r>^ ^l^g jgg, ij^ differentiated 



from the rest of the wing 

 membrane. In BiplujUa 

 this tendency is carried to 

 a yet higher degree— the 

 region named being cov- 

 ered with liair. The sepa- 

 ration of the fur of head 

 and neck from that of the 

 trunk is as conspicuous in 

 DipliyUa as elsewhere in 

 the order. The great length and richness of the fur on the side of the 

 neck (extending as far as the shoulder) is remarkable. 



The muzzle is flat and square, without excavations or incisions on 

 the upper border, and is not separated interiorly from the lip. Con- 

 tinuous with the lower outer angle is a ridge leading to the great cres- 

 centic gland-mass, constituting a coarsely setose ridge. The space 

 directly back of the muzzle is occupied in one specimen (No. G990, V. S. 

 N. M.) by slight extension from the right side of the gland-mass. The 

 left side is witliout such occupation. In the other specinuMi (No. 0440, 

 IT. S. N. M.) the space is tilled with a minute elevated mass of glands, 

 which extends across and unites the two great crescentic gland-masses. 

 Dobson states that "a raised (?) glandular ridge forms a semicircle 

 between and behind the eyes, somewhat broader on the sides, but not 

 thickened m the center." This "center" answers to the transverse 

 rid-e back of the muzzle in specimen No. 9440, U. S. N. M., and which 

 is seen to be imperfect in No. 0090, IL S. N. M 41ston figures the head 

 with this trausverse crest well developed. 



/JV.V 



Fig.l. 



DIPHYLLA ECAUDATA. 



V of face and liead. Tw.ce u: 



