148 BULLETIN 43, UNITED STATES NATIONAL MUSEUM. 



phalanx. The membrane is drawn evenly across the dorsal borders of 

 the digit, so that the bones project palmad only. The third metacarpal 

 bone is here as distinct as any others of its series. The proximal fourth 

 of the fifth metacarpal bone is concealed by i)almar folds. 



When the lines of the membranes are studied they are seen to be 

 much the same as in A. cinerea, with the exception of the intercostal 

 lines, which are more distinct than in that species, and the horizontal 

 limbs of the triceps fascicle system are farther apart. The third 

 interspace is without predigital lines. The terminal digit of the fourth 

 finger is without projecting lobe; that of the fifth finger is minute. 

 The prebrachim with two elliptical thickenings in the line of the ten- 

 don of the occipito-pollical muscle; one of these lies at the shoulder, 

 the other along the line of the forearm. 



/SAjf?/.— The brain caseismuch elevated posteriorly and abruptly inclines 

 downward toward the face; no depression on vertex between mesen- 

 cephalon and meteucephalon. Processes and crests as a rule produced. 

 The sagittal temporal crest is short and nearly confined to the interval 

 between the meteucephalon and the mesencephalon. The posterior 

 temporal ridge is well defined and extends obliquely from the end of 

 the sagittal, thus leaving a large triangle between the two crests 

 and the occipital crest. The anterior temporal crests are faintly de- 

 fined. The meteucephalon is a third of the entire length of the head. 

 The swelling of the protencephalon is distinctly seen on the vertex. 

 The vertex of the face is provided wnth a wide groove its entire length; 

 there is no nasal eminence. A rounded ridge is seen on each side on 

 the line of the single incisor. The outer wall of the infra-orbital canal 

 is elevated into a tnbercle. The lachrymal bone bears a distinct though 

 small spine. The fronto-maxillary iutiation is moderate and the inner 

 wall of the orbit flat. The zygmotic arch is slender and of uniform 

 width, i.e., is without elevation of the upper border. The paroccipital 

 process is nearly as long as the occipital condyle; the mastoid process 

 is nearly as long as the paroccipital; thelowerborder of the interval is 

 deeply notched. The tympanic ring is complete. Tlie angle of the 

 lower jaw is entirely outside the condyle, as seen from above. The 

 masseter impression is not defined interiorly and reaches the inferior 

 impression of the horizontal ramus. 



The details of the cribriform plate and the ethinoidal turbinal plates 

 are as follows : 



The encranial surface presents the septoturbinal foramina placed in 

 a row along the anterior half of the space of the same name. The oi^en- 

 ings of the ectoturbiual surface are in a direct line with the foregoing, 

 and both are depressed below the general surface. The foramen for 

 the first endoturbinal is seen lying at the bottom of the conspicuous dc" 

 pi'ession near the crista galli. The foramina are everywhere at the 

 sides of the encranial surface. Seen fjoni the nasjil as])ect the ectotur- 

 biual seems to be nearly the length of the first endoturbinal, and is com- 



