2 BIOLOGICAL SOCIETY OF WASHINGTON. 



The following characters will serve to distinguish the species 

 from its allies : 



VESPERTILIO CILIOLABRUM* sp. nov. 

 (Type No. 2797 female ad., Merriam Collection). 



Dental formula : i. ^ c. I=L' pm. g' m. g-' =-i? = 38- 



The outer upper incisor of each side slopes forward and 

 inward parallel to the inner, contrary to the rule in the genus 

 Vespertilio, in which these teeth usually are divergent ; cusp 

 of inner upper incisor bifid, the anterior point being larger. 

 First upper premolar small and crowded against (and usually 

 somewhat internal to) the canine ; second upper premolar 

 minute and wholly internal to the tooth-row so that it is not 

 visible from the outside except in immature individuals ; third 

 premolar very large, nearly or quite equal to canine. Middle 

 lower premolar smallest ; posterior largest. 



Sides of upper lip fimbriate. Glandular prominences be 

 tween eyes and nostrils moderately developed. Tip of ear 

 laid forward extends to end of muzzle. 



The calcaneum reaches about half-way from the foot to the 

 tip of the tail ; the postcalcaneal lobule is large for a Ves- 

 pertilio ', the calcaneum ends in a projecting tooth or lobule. 



The form of the ear is somewhat intermediate between that 

 of V. nitidus and that of V. nigricans : Internal basal lobe 

 slightly rounded ; middle three-fourths of anterior margin 

 strongly conyex ; tip shortly rounded off, forming a small, pro 

 jecting lobe posteriorly, beneath which the outer border is 

 sharply emarginated for about one-third of its entire length ; 

 bottom of emargination straight or slightly convex ; below this 



*The specific name ciliolabrum refers to the fringe of hairs along the 

 sides of the upper lip. 



