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Show 1879.] ANATOMY OF HY^SNA CROCUTA. 97 tending forwards for about one inch from a mesial raphe in the neck, this muscle is inserted into the whole length of the shaft of the humerus, from the bicipital groove down to the elbow. The fibres are easily separable into a superficial and a deep stratum, thus corresponding closely to the arrangement in H. striata. In the Civet the pectoralis major, as in the Dog, consists of three strata, whilst its insertion is much more limited than in H. crocuta. Pectoralis minor wanting, as in Carnivores generally1. Deltoid consists of two parts-one, narrow, from the tip of acromion, and a second, wider, from the fascia covering the infraspinatus ; they are inserted together into the deltoid ridge of the humerus. The so-called clavicular portion of the deltoid we describe with the levator humeri; but including this element, the deltoid of H. crocuta is evidently the same as Meckel describes in H. striata, and agrees with what we find in Viverra. Douglas describes the deltoid in the Dog as we do in H. crocuta, the acromial and scapular portions, however, not being so easily separable. Levator humeri proprius (Douglas) arises by two heads-one, thin, from the anterior half of the neck, dorsal mesial line, and a second, riband-like in character, from the mastoid process. The heads unite in front of the shoulder-joint; and the resulting belly is inserted into the lower end of the shaft of the humerus, in front of the biceps. This corresponds to the cephalo-humeral described by Murie in H. brunnea, whilst by Meckel it is in H. striata regarded as a portion of the double trapezius. The subscapularis, from the venter scapulce (except so much as affords attachment to the serratus magnus) to the smaller humeral tuberosity. Infraspinatus and supraspinatus are both strong and well developed ; they, as well as the subscapularis, present no deviation from the usual arrangement. Teres minor is small, but is distinct from the infraspinatus, as in Civet and Dog. A levator scapulce (trachelo-acromial) arises from the inferior border of the transverse process of the atlas, and runs to the acromial process of the scapula. The same arrangement is mentioned by Meckel in H. striata and Viverra, and by Douglas in the Dog. Teres major is from the upper half of the posterior margin of the scapula. Its insertion unites with that of latissimus dorsi, as in Civet. The biceps is single-headed, attached above to the upper border of the glenoid cavity, and below to the inner borders of both radius and ulna. In respect of origin it agrees with H. striata and Dog. In the Civet the biceps is coracoid in origin, and entirely radial at its insertion. Brachialis anticus, from almost the whole length of the posterior surface of the shaft of humerus, winds round the outer side of the lower half of that bone, and is inserted into the upper two inches of the internal border of the ulna. The arrangenent is essentially the same in the Civet and Dog. 1 Cuvier, Lecons d'Anat. Comp. vol. i. p. 256. PROC. ZOOL. Soc-1879, No. VII. 7 |