134 BULLETIN 42, UNITED STATES NATIONAL MUSEUM. 



Membranes. — Intercostals four in number. The coraco-bracliialis 

 fascicle appears near the axilla and becomes vertical a little beyond the 

 elbow. The triceps fascicle system with a single superior oblique and 

 a single vertical inferior branch. The line above the main trend of the 

 nerve as in A. fuscus. The fourth interspace as in this species except 

 that the postdigital appears at the proximal sixth of the fourth metacar- 

 pal bone. In one siiecimen it was absent. The oblique tibial and 

 pubo tibial lines as in this species. In No. 4378 the Hues in the fourth 

 interdigital space arise from the digits, the postdigital from the proxi- 

 mal third and the predigital from near the middle. 



SkuU. — The sagittal crest is defined its entire length. The posterior 

 temporal ridge is trenchant, limiting a small triangle. The anterior 

 temporal ridge is also well defined and ends on the orbital ridge which 

 is sharply outlined, and is continuous with an oblique line which crosses 

 the flat inner wall of the orbit. The fr on to-maxillary inflation is rudi- 

 mental, — the least developed in any of the species. The face-vertex is 

 without depression in some examples; in others it is shallow, and less 

 than half the length of the region. (Such specimens may not be en- 

 tirely mature.) Two shallow depressions overlie the maxilhie. The 

 facial infraorbital foramen lies over the interval between the second 

 premolar and the first molar. The anterior nasal aperture ends ou the 

 line of the anterior border of the second premolar. The paroccipital 

 process is acuminate and projects downward no farther than the level 

 of the inflated mastoid. The interval between these two processes is 

 concave and incised below. The tympanic bone is incomplete above 

 the head of the malleus intervening. The coronoid process lies above 

 the level of the condyle and slightly exceeds the width of the adjacent 

 horizontal ramus. The massetric impression reaches the lower margin 

 of the ramus. The angle is small, truncate, and slightly produced be- 

 yond the line of the condyle. 



The encranial surface is about one-third the area of the entire region, 

 the cribriform plate marked as follows: First, a single opening is seen 

 on the sphenoturbinal surtace; second, two openings on the ectoturbi- 

 nal surface; third, a relatively large depression on the endoturbinal, 

 containing two openings, well to the lateral aspect, for the first endo- 

 turbinal plate. 



The nasal surface exhibits a single ectotiirbinal plate. It is a little 

 less than one-half the length of the first endoturbinal, is directed al- 

 most vertically downward, the swollen upper border looking outward. 

 The lateral surface is concave, deflected outward as far as the tip of the 

 first endoturbinal. It is slightly concave above. The free portion is 

 acuminate, reaching as far as the level of the canine tooth. The second 

 plate is as in V.fuseus, but not so much narrowed at the base. The 

 third is a mere rounded nodule. 



MaxUlary teeth. — The incisor slender, simple, with entire cingulum 

 vertical on border of palatal notch ; a small space between it and the 

 canine. The palatal surface of the canine concave, broad; posterior 



