598 GEOLOGICAL SUEVEY OF THE TEREITOEIES. 



ferior margins of tbe succeeding segments are thickened, but tlie com- 

 X>ressed form remains, tbe section being triangular. 



Tbe scapula is large for tbe size of tbe animal. It bas an approxi- 

 mately triangular form, tbe base being superior. Tbe posterior angle is 

 rigbt,. but tbe anterior regularly rounded. Tbe apex supports tbe gle- 

 noid cavity on a neck wbicb is contracted by a sb allow excavation of 

 tbe anterior margin. Tbe latter is bounded next tbe 'glenoid cavity by 

 tbe sbort obtuse coracoid, wbicb stands a-isbort distance above tbe artic- 

 ulation. Tbe spine is long, ratber elevated, witb a regular convex border 

 curved backward. 



Measureme7its. 



M. 



Length of three sternal segments 0. 147 



Length of first sternal segments 084 



Depth of first sternal segments in front 044 



Width of first sternal segments below 004 



Width of third sternal segments 015 



Length of scapula, (median) 215 



AVidth above, (greatest) 130 



Width of neck 036 



Width of glenoid cavity 035 



Humerus. — Tbe bead is directed a little inside of directly backward. 

 Tbe bicipital groove is very deep and tbe inner tuberosity large and 

 directed forward. Tbe external tuberosity is mucb larger, as usual in 

 tbis grouj) of ungulates, and rises in a book-like apex above tbe lev^el of 

 tbe bead. Tbe external bicipital ridge is lateral, and not very promi- 

 nent, extending on one-third tbe length of the shaft. The shaft is mod- 

 erately compressed at the middle, but transversely flattened below. It 

 is nearly straight. Tbe condyles are narrow, and the inner and outer 

 tuberosities almost wanting ; their position marked by shallow concavi- 

 ties. Tbe external continues in a lateral crest which turns into the 

 shaft below the lower third. Tbe inner condyle is both tbe widest and 

 most prominent ; tbe external has its carina at its middle, and its ex- 

 ternal trochlear face oblique and narrow ; narrowest behind. The ole- 

 cranar and coronoid fossas are deep and produce a small supra-condylar 

 foramen. 



Tbe ulna exhibits a large and obtuse olecranon, concave on tbe ex- 

 ternal face. Its glenoid cavity is narrowed and elevated behind ; in 

 front it widens, and there the ulna receives the transverse proximal end 

 of tbe radius, wbicb overhangs it on both sides, leaving the little eleva- 

 tions of the rigbt and left coronoid processes about equal. Tbe vertical 

 diameters of tbe shaft of the ulna are about equal throughout. Its 

 section is triangular, tbe base being next the radius for tbe proximal 

 tbitd. This is. followed by an edge next the ulna, and tbe base of tbe 

 section is on the outer inferior aspect, on account of tbe direction (jf an 

 angle from a short distance beyond the outer coronoid process to the 

 base of tbe ulnar epiphysis, where it disappears. Distally there are 

 two other very obtuse ridges above tbis one. The extremity bears two 

 facets — the larger for the cuneiform, the smaller for tbe pisiform bone. 



The radius is throughout its length a stouter bone than tbe ulna and 

 bears much the greater part of the carpal articulation, viz : witb the 

 scaphoid, lunar, and part of the cuneiform bones. Tbis articulation is 

 transverse to that of tbe ulna, which is thus at one side of and behind 

 it. The bead is a transverse oval in section, the narrower end outward. 

 Tbe articular face consists of one and a half trocblese, the latter wider 

 and internal. The shaft is a transverse oval in section, with an angular 



