1881.] ANATOMY OF THE ERINACEID.aj. 395 



Of the muscles which are attached to the humerus, tlie latissimus 

 dorsi is well developed ; it is inserted, as usual, in connexion with 

 the teres major, and gives otF near its insertion a broad but thin 

 dorso-epitrochlearis, wliich arises from its lower margin by a ten- 

 dinous aponeurosis. 



Pectoralis major is extensive in its origin. It is divisible into 

 clavicular and sternal portions, the former from the outer half of the 

 clavicle ; the latter, from the sternum and tlie cartilages of the ribs, is 

 again divided into an anterior and posterior part. The former is 

 narrow, arising from the sternum at its anterior extremitv, and from 

 a raphe common to it and its fellow of the opposite side, which 

 extends beyond the sternum, covering the origins of the sterno- 

 mastoid muscles ; each muscle passes directly outwards to its inser- 

 tion into the humerus. The latter, or posterior part, is by far the 

 largest, arising from the whole length of the sternum behind the 

 preceding, from the sternal extremities of the costal cartilages, and 

 from fascia connected with the sheath of the rectus ; the muscular 

 mass thus formed divides into four fasciculi, two superficial and two 

 deep: the former are inserted into the middle third of the humerus ; 

 of the latter the anterior or smaller fasiculus (?«. sterno-clavi- 

 cularis) is inserted into the greater part of the outer third of the 

 clavicle, the posterior or larger into the greater tuberosity aud 

 neck of the humerus. 



The peculiar anomaly of the same muscle being inserted into and 

 also arising from the same bone, suggests whether the so-called 

 clavicular part of the great pectoral should not be considered a 

 separate muscle, which might be termed clavicuJo-humeralis. 



The very complete separation of the anterior division of the sternal 

 part of the muscle from the other parts, and the united origins of 

 the muscles of the opposite sides which compose this part, and 

 which extend for a considerable distance beyond the anterior extre- 

 mity of the sternum, recall the well-known similar conditions in 

 Talpa. 



The teres major is well developed ; but there is no trace of a 

 tens minor. The tricejjs is enormous in comparison with the size of 

 the animal ; it arises by three heads, a scapular and two humeral. 

 The biceps arises by a single head from the scapula above the glenoid 

 cavity, and is inserted into the ulna ; the brachialis anticus, on the 

 other hand, is inserted into the radius. There is no trace of either 

 coraco-Lrachialis longus or lirevis. 



Of the forearm-umscles the supinator longus is absent, the supi- 

 nator brevis present but very small ; the pronator radii teres is 

 inserted by a broad muscular expansion into the middle part of the 

 lower third of the radius ; the extensor dicjitorum communis and the 

 extensor minimi dic/iti are united in the arm, the muscular mass 

 dividing into two tendons, which cross the carpus, the smaller of 

 these representing the tendon of the latter muscle, being distributed 

 by slips to the fifth and fourth digits ; the larger divides into four, 

 which are distributed to tlie three middle toes. The extensor 

 sccundi internodii pollicis et extensor indicia is small, arising by a 



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