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Show 392 DR. B. C. A. WINDLE AND MR. F. G. PARSONS ON THE [Apr. 6, Ursus americanus (XX.), which is interesting, because that animal has a two-headed biceps and also because in the specimen of Procyon lotor dissected by us (53) the small coracoid head could be separated by a little tearing from the rest of the muscle and was found to end in the fascia of the forearm. So far as we are able to generalize from the material at our disposal, we should say that in the Carnivora a single-headed biceps inserted into the radius is the normal arrangement, but that the Ursidae are characterized by a double-headed muscle, a condition that is approached by the nearly related Procyonidae, e. g. Procyon lotor (53) and Cercoleptes (61, 62). Coraco-brachialis.-This muscle usually rises by a small rounded tendon from the tip of the minute coracoid process; it soon becomes fleshy to be inserted into the humerus near its surgical neck, having passed above (over the cephalic border of) the latissimus dorsi tendon (see fig. 8, p. 390). This coraco-brachialis brevis or rotator humeri was the only part of the muscle seen in the following animals :-Feles leo (1, 1 a), F. tigrls (3), F. pardus (5), F. catus (6), F. caraccd (8), Cyncelurus jubatus (9), Cryptoprocta (10), Viverra civetta (12, 13, 14), Genetta (16), Paradoxurus (21), Herpestes (24), Proteles (25), Hycena striata (26, 28), H. crocuta (29), Canis familiaris (31) (in four other dogs Macalister describes the coraco-brachialis as present, but does not say wdiich parts ; he would probably have made a note had there been anything more than the rotator humeri), Canis aureus (41), Procyon lotor (53, 54, 55), P. cancrlvorus (57), Nasua (58,59, 60, 60«), Cercoleptes (61), Galictis vittata (63). In Straus-Durckheim's cat a delicate tendon rose with the rotator humeri and passed down ventral to the latissimus dorsi to be inserted into the lower third of the humerus just above the supra-condylar foramen (IL). In four specimens of Ursus americanus (48, 49, 50, 52) a coraco-brachialis longus was present in addition to the rotator humeri; in one of these Shepherd (XX.) describes the long part of the muscle as being pierced by the musculo-cutaneons nerve, while, in another, Testut (XXIII.) mentions that the brevis was double. In a fifth specimen of the same animal Haughton (XXL) describes the rotator humeri and then speaks of a coraco-brachialis accessorius, " which," he says, " is like the gemelli " ; whatever may be the exact meaning of his description, it is evident that more than one part of the muscle was present in his case. Both Ursus maritimus (45) and U. arctos (47) resemble the rest of the Bears in having both the brevis and the longus. The Procyonidae, as has been shown, usually have tbe normal carnivorous arrangement, but Perrin's specimen of Cercoleptes (62) differed from our own in having the bear-like double muscle. Among the Mustelidae, Gallctls harbara (64) and Mustela folna (67) are bear-like. In four specimens of Lutra vulgaris (74, 75, 76, 77) the muscle was entirely absent, while in a fifth described by Haughton (XXXIV.) no mention is made of it, though all the surrounding muscles are spoken of. In Lutra cinerea Macalister (XXXVII.) describes the brevis as being present on the left side but absent on the right. In two specimens of Ictonyx |