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Show 386 DR. B. C A. WINDLE AND MR. F. G. PARSONS ON TflE [Apr. 6, of the posterior thoracic spines, usually from the 4th or 5th to the last, from the lumbar aponeurosis, and sometimes from the last three ribs. No muscular fibres can be traced to the ilium. At its insertion it usually divides into two layers, the anterior of which unites with the dorso-lateral panniculus to be inserted deep to the pectoral into the pectoral ridge of the humerus; while the deep is more or less united with the tendon of the teres major, though it is seldom twisted round that tendon as it is in the Rodents and in Man. These two parts enclose the biceps. In Cyncelurus (9), Procyon (53, 54), Mustela putorius (65), and Lutra (74) it rises from the last three ribs ; in Canis (31) from the last two; in Viverra civetta (12), Genetta (18), Proteles (25), Hycena crocuta (29), and H. brunnea (30) it has no attachment to the ribs. In the other animals, unfortunately, no record has been kept as to whether it rose from ribs or not. Procyon cancrivorus (57) is remarkable for having the muscle divided into an anterior and posterior part; the former, wdiich is the larger, joins the teres major and gives off the dorso-epitroch-learis, while the latter joins the dorso-humeral panniculus and is inserted with it deep to the pectoral. Dorso-epitrochlearis.-This muscle shows frequent variations in its size and attachments; its usual origin, as in most other animals, is from the latissimus dorsi just before the latter becomes tendinous ; it then runs down the inner side of the triceps to be inserted into the inner side of the olecranon process as well as into the fascia of the forearm (see fig. 8, p. 390). It is supplied by the musculo-spiral nerve. In the Cat, Mivart (I.) describes two muscles which he calls external and internal, the former rising from the spine of the scapula, the latter from the surface of the latissimus dorsi; these unite before their insertion. Straus- Durckheim, in his w-ork on the Cat (II.), only records the internal of these. In one specimen of Paradoxurus (19) the muscle rose from a sling over the axillary vessels reaching from the latissimus dorsi to the biceps. In Ursus americanus Shepherd (XX.) describes it as rising from the axillary border of the scapula as well as from the surface of the latissimus, and says that it receives slips from the panniculus and teres major. Macalister describes two muscles in Galictis harbara (IX.), but one of them is evidently a structure to which we shall have to call attention under the head of the triceps. Rhomboids.-Instead of the rhomboideus major and minor of human anatomy we find in the Carnivora one plane of muscle risiug from the curved line of the occipital bone and the ligamentum nuchae, the rhomboideus anterior, and another rising from the spines of the anterior thoracic vertebrae, which it would be convenient to speak of as the rhomdoidens posterior. The insertion is into the vertebral border of tbe scapula. Occasionally the posterior edge of the r. anterior is continuous with the anterior edge of the posterior, but more often there is a distinct interval between them. It is usual for many writers to speak of only that part of the muscle which is attached to the skull as a rhomboideus |
