OCR Text |
Show 1882.] ANATOMY OF ERETHIZON DORSATUS. 281 half of the deltoid crest of the humerus, being much connected with the adjacent part of the deltoid, and a portion running on to fuse with the brachialis anticus. The sternocleido-mastoid, arising as usual, is inserted into the antero-posteriorly extending ridge just behind the opening of the external auditory meatus. The levator clavicula arises, by a strong tendon, from the hypa-pophysial tubercle on the middle of the ventral surface of the atlas. Fig. 9. ' P The lumbo-sacral plexus of Erethizon dorsatus. Ant. cr, anterior crural nerve; Or. Sc, great sciatic nerve; L, last lumbar vertebra; I. Sc, small sciatic nerve; Ob, obturator nerve ; P, pelvis; S1, first sacral vertebra. Expanding in a fan-shaped manner, it is inserted into fascia investing the acromion and the greater tuberosity of the humerus, its fibres mingling with those of the dorsal part of the panniculus camosus. The latissimus dorsi sends on a dorso-epitrochlear to the olecranon. PROC. ZOOL. Soc-1882, No. XIX. 19 |