| OCR Text |
Show 1897.J MYOLOGY OF THE TERRESTRIAL CARNIVORA. 401 •pictus (44) Pagenstecher says that the " supinator brevis is absent, as in the cat aud dog "; in this instance supinator longus, not brevis, must surely have been meant. There can, we think, be little doubt that in the Canidae the muscle is usually absent. In the Ursidae the supinator lougus is very constantly present; it is so in four specimens of Ursus americanus (48, 49, 51, 52), and one of U. marltlmus (45), of which we have records. In the Procyonidae it is present in three specimens of Procyon lotor (53, 54, 55), in Nasua (60), and Cercoleptes (61). Among the Mustelidae it is present in Galictis vittata (63), 67. harbara (64), Mustela putorius (65), M. foina (66). Ictonyx libyca (70), and Meles taxus (71, 72). In four specimens of Lutra vulgaris the muscle was found to rise from the humerus as far up as the neck (74, 75, 76, 77): it was also present in L. cinerea (78). To sum up, the supinator longus is present in the Felidae with the exception of Cynceluras, the A^iverridae, the Ursidae, the Procyonidae, and the Mustelidae. It is usually absent in the Hyaenidae with which Proteles agrees, and in the Canidae. Extensor carpi radialis longior and brevior.-The point on which the greatest stress is laid in descriptions of these muscles is as to whether they are completely separate or more or less blended at their origin. W e are not inclined to pay much attention to this distinction, since it has frequently been our lot to find muscles, apparently inseparable, separate easily with a little traction. The origins of the muscles are the same as those described in human anatomy, the longior rising from the supracondylar ridge, the brevior from the condyle. The insertions are respectively into the shafts of the metatarsal bones of the second and third digits. The following are the only variations with which we have met:- In Hgcena striata (26, 27) the two tendons are united by a transverse band about the level of the wrist. In Lutra cinerea the extensor carpi radialis longior divides, and one part is inserted on each side of the base of the second metacarpal, the inner one being connected by a transverse slip with the tendon of the extensor carpi radialis brevior. Extensor communis digitorum.-This muscle rises from the back of the external condyle, and is inserted into the middle and distal phalanges of the second, third, fourth, and fifth digits; on the dorsum of the hand the tendons are connected by broad, thin vincula. This insertion is most constant in all the Carnivora, the only exceptions with wdiich we have met being a dog (32) dissected by Haughton, where the tendons are described as going chiefly to the fourth and fifth digits, and our own specimen of Herpestes (24), where the slip to the fifth digit was wanting. Extensor minimi digiti.-This muscle rises from the external condyle and, in the dorsum of the hand, usually divides into three tendons which pass to the medius, annularis, and minimus, uniting on the backs of the digits with the expansions of the extensor communis. In the following animals tendons to these three digits were present:-Felis tigris (3), F. catus (6), Crgptoprocta (10,11), Viverra |
