A MONOGRAPH OF THE BATS OF NORTH AMERICA. 179 



The distal end of the radius is furnished ^vitli a large median process. 

 Ulna with proximal end not anchylosed to the radius, but having an 

 exceedingly delicate throat-like shaft which joins the radium at .junc- 

 tion of middle with the distal, viz., at 45"'™ the ramius being 72""" long. 

 This is best seen in the young. The distal ulna element is united to 

 the radius, forming with it a perforate quadrate plate which bears a 

 minute perforation. The distal border of the plate is notched. 



A sesamoid dorsad to first row of carpal bones; a second sesamoid on 

 the fourth metacarpal, which is united to centrale (or magnum) by a 

 ligament; a third sesamoid on fifth metacarpal at proximal end; it is 

 united to the bones of the first row by a ligament. 



Carpus. — The concavo-convex trapezium much larger than the small 

 tripartite trapezoid, and overlapping it. Magnum subcordate unci- 

 form Avith coarsely spinose facet for the fourth metacarpal, but is plain 

 and simple for articulation with the fifth metacari)al. Unciform, suiall, 

 irregular. Pisiform not extending on shaft of the hfth metacarpal. 



Metacarpus with first metacarpal, with axial facet for articulation, 

 with a lateral facet of the second metacari)al. Second metacarpal with 

 a large angulated head which is directed toward the fifth; the fifth 

 metacarpal has a corresponding angulation which is directed toward 

 the second; this arrangement greatly strengthens the palmar aspect of 

 the carpus. The bone is compressed Avith sharj) palmed keel nuich 

 smaller than any of the series. 



The differences in the length of the metacarpal and phalangeal ele- 

 ment are seen in the table of measurements. 



No keel is seen on the sternum. 



Eibs are thirteen in number — the twelfth and thirteenth being widely 

 deflected and having much larger interspaces than the others. The 

 sacrum has three elements. 



Innominate with concave dorsum anchylosed to the sacrum and to 

 each other at the pubis. 



Femur. — Internal trochanter with minute spine; external trochanter 

 with rugose longitudinal ridge extending on proximal fourth of shaft. 

 The line of top of the external trochanter carried across shaft lies just 

 below head and, if i)roduced, intersects the lower border of the free 

 end of the internal trochanter. 



Tibia, with globose spine, posterior surface of shaft near condyle 

 depressed for flexon of toes. Fibula entire; prox end with glocose ex- 

 tremity; distal end the larger, with well-defined malU'olus. Clavicle 

 widest to mesal half. A distinct facet is seen for articulating with the 

 first costal cartilage. 



Measurement!^. 



MilHiiictora. 



Head and body (from crown of head to base of tail) 70 



Length of arm 35 



Length of forearm 67 



