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Show 1897.] MYOLOGY OF THE TERRESTRIAL CARNIVORA. 393 (69, 70) the muscle was also absent, as was the case in Mustela putorius. In Meles (71, 72) the coraco-brachialis is a single muscle and is inserted into the middle third of the humerus, ventral to the insertion of the latissimus dorsi. Unfortunately no mention is made of the relation of the muscle to the musculo-cutaneous nerve, but it looks very much like the only instance of a coraco-brachialis medius which we have met with in Carnivora. Brachialis anticus.-In its typical arrangement this muscle seems to consist of two parts: (1) a long head rising from the back of the surgical neck of the humerus aud winding round the outer side of that bone to reach the front, forming in its passage the musculo-spiral groove; (2) a short head rising from the anterior border of the lower half of the humerus. These two heads are inserted together into the coronoid process of the ulna. In the Carnivora the long head is always present and is most constant in its attachments, while the short head we have not met wdth at all. W e believe that the proper nerve-supply of the long head is the musculo-spiral and that of the short head the musculo-cutaueous ; in two or three Carnivora, in which we have carefully looked for this point, we have only found a branch from the musculo-spiral, but further observation is necessary before a definite statement can be made. Triceps.-This muscle shows a good deal of variation in the number of bundles into which the humeral portion is divided, though we are not inclined to regard these divisions as of any classificatory importance ; as an example of this we may quote the case of the Racoon, of which we have three records. In the first of these (53) we were able with great ease to distinguish five heads, the external of human anatomy being double, while the part of the internal head which rose from the bridge of bone over the supracondylar foramen was separate. On comparing this with Allen's description (XXVI.) we find only four heads mentioned, the one from the supracondylar bridge not being distinct. In Procyon cancrivorus (57) only the three heads described in M an were noticed. The middle or long head, with one exception, is quite constant and usually rises from the glenoid half of the axillary border of the scapula. Among the Felidae there are altogether five heads in F. catus (6). In the Viverridae, Cryptoprocta is described as having four heads by Beddard (VII.), but in our own specimen we noticed an extra scapular head rising from the dorsal part of the scapular spine and from the fascia over the infraspinatus. In Viverra civetta (13) and Herpestes (24) four heads were seen, in two specimens of Genetta five (16) and four (18) respectively. In Proteles (25) Watson found five heads, one coming from the spine of the scapula and probably corresponding to the spinous head in Cryptoprocta. Among the Hyaenidae only three heads were seen inH. striata (26), but in H. crocuta (29) there were four, the external head being double. Among the Canidae, we found five heads in C. familiaris (31), the long head being double (see fig. 8, p. 390); the same arrangement is figured by Cuvier and PROC ZOOL. Soc-1897, No. XXVI. 26 |
