A MONOGRAPH OF THE BATS OF NORTH AMERICA. 165 



fur extends on the membranes from a point at the proximal third of the 

 humerus to the distal two-thirds of the femur and is thicker along the 

 margin than where it is continuwns with tlie body. On the venter the 

 fur is intermediate in shade between that of the back and the side of the 

 trunk. It is either unicolored or barely white at the base. The pre- 

 brachial membrane is naked or furnished with a small pntcli of hair. 



The face is naked over the dorsal surface except in the space be- 

 tween the median border of the auricle and the nostril where a number 

 of long 3""" to 4""" stout bristles are found.* In the female not in- 

 frequently a whitish diffused patch is seen on each side of the neck 

 near the lower jaw. A few long white hairs adorn the pubis. Occa- 

 sionally the male has a patch similar in color to the above growing on 

 the post-mental space. 



Memhranes. — The entopatagium without markings from the inter- 

 costal or lumbar nerves. The line of the coraco-brachialis fascicle be- 

 comes apparent at the middle of the humerus, passes vertically down- 

 ward medianly to the elbow, and divides, at lower two-thirds of the 

 membrane, into two branches. The lower runs forward to a iioint lat- 

 eral to the elbow, i. e., in advance of the joint. The triceps fascicle 

 system with a plesh of superior branches. The terminal part of nerve 

 abruptly deflected downward. 



The first oblique band at the radiometacarpal angle is attached to 

 the first metacariial bone. It crosses the palm obliquely, and reaching 

 the mesopalafium lies for 4'"°' close to and parallel with the radius. The 

 pouch is distinct. The tendon of the palmar interosseus muscle of the 

 fifth finger makes no impression upon the membrane. A broad, dusky 

 band, apparently due to the membrane becoming contracted in this 

 line, extends obliquely from the lower end of the tibia to the wrist. It 

 is conspicuously seen in all specimens which are held up to a strong 

 transmitted light. 



The fourth interspace shows a nerve appearing at the angle ante- 

 riorly. This soon divides into two branches, a posterior and an ante- 

 rior. The posterior passes obliquely across the membrane to reach the 

 fifth finger at the distal third, where it disappears. Before doing so it 

 yields a branch, which is distributed to the posterior half of the mem- 

 brane. The anterior nerve keeps close to the fourth finger. At its 

 proximal fourth it is lost in the contour of the bone. Just before its 

 termination it sends oft" a large posterior branch, which, supplies the 

 anterior of the interspace. In the third interspace a long main nerve 

 is seen dividing into two branches. In the second interspace a poste- 

 rior nerve appears at the proxinml third of the first phalanx of the 

 fimrth finger, and an anterior fi-om the proximal third of the first pha- 

 lanx of the third finger. The ecto])atagium is attached on the distal 

 end of the second phalanx of the fifth finger, while the mesopatagium 



*The l)ristles about the nostrils have hecn neglected in describinj; species of Xi/cii- 

 nomus. They are conspicuous in X. brasilicnsis, while almost absent in N. pUcalus. 



