45. One minute incisor before each upper canine 46. 

 Two minute incisors before each upper canine 50. 



46. Four upper cheek teeth on each side 47. 

 Five upper cheek teeth 48. 



47. Incisors separated by less than the width of one; frontal region some- 



what concave 



Tadarida Frectailed Bat 

 Incisors separated by about four times the width of one; frontal region 

 convex 



Lasiurus Red Bat and Hoary Bat 



48. Profile convex; gap between tips of incisors less than width of incisor at 



base 



Antrozous Pale Bat 

 Profile slightly concave before orbits; gap between incisors more than 

 twice the width of incisor 49. 



49. Length of skull only twice its height; upper incisor touching canine 



Dasypterus Yellow Bat 

 Length of skull three times its height; upper incisor not touching canine 

 7\[>'ct!ce!us Rafinesque's Bat 



50. Six upper cheek teeth on each side 



Myotis House or Little Brown Bat 

 Four or five upper cheek teeth 5L 



5 1 . Four upper cheek teeth on each side 



Eptesicus Brown Bat 

 Five upper cheek teeth 52. 



52. Cranium high; skull length about twice the height 



Corynorhinus Lump-nosed Bat 

 Profile fairly straight; skull length about two and one-half times the 

 height 53. 



53. Skull about three-fourths of an inch long; six lower cheek teeth on each 



side 



Lasionyctens Silvery Bat 

 Skull seldom over one-half inch long; five lower cheek teeth 

 Pipistrellus Pipistrelle Bat 



54. Bulla well developed; ten teeth in each half of upper jaw, eight below; 



anterior teeth, after the first, varied in size 

 Scalopus Common Mole 

 Bulla only slightly developed; eleven teeth above and below on each 

 side, the anterior ones, after the first, about equal in size 55. 



55. Profile slightly concave in frontal region; first upper incisor projecting 



anteriorly 



Condylura Star-nosed Mole 

 Profile slightly convex; first upper incisor directed downwards 56. 



56. Fourth upper tooth on each side almost as long as the first; bulla scarcely 



evident; no auditory meatus (bony tube to ear) 

 Parascalops Hairy-tailed Mole 



529 



