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Show 1897.] MYOLOGY OF THE TERRESTRIAL CARNIVORA. 403 (64), while in Mustela putorius (65) and Lutra (74, 77, 78) it reaches as low as the third quarter. In Meles (72, 73), however, it only goes as far as the middle of the radius. Extensor ossls metacarplpollicis.-This muscle is always present in Carnivora and is constant in its attachments; it rises from the dorsal surfaces of the radius and ulna, especially the latter, and is inserted into the base of the metacarpal bone of the pollex and often into the radial sesamoid bone near it. In Procyon lotor (53) and Galictis harbara (64) slips were given to the trapezium. In the former animal and in Viverra civetta (12) the highest fibres rose as far up as the olecranon. Extensor digitorum profundus.-Instead of describing the extensor secundi internodii pollicis and extensor indicis as two separate muscles, we have found it more convenient to follow the example set in Bronn's ' Thierreich M and to speak of them under the above heading. W e do not propose to include tbe extensor ossis metacarpi pollicis with the other two, as it is not an extensor of a digit but of a metacarpal bone. The extensor primi internodii we have never seen in the Carnivora. The origin of the extensor profundus is from the dorsal surface of the ulna, below that of the extensor ossis metacarpi pollicis, as wcdl as, sometimes, from the dorsal surface of the radius. In the Felidae the muscle goes to the pollex and index as a rule ; this is the case in Fells leo (1), F. tigris (3), F.pardus (4), and F. catus (6). In Cyncelurus (9), however, no slip goes to the index. Among the Viverridae the insertion is very constant and is the same as it is in most of the Felidae : Cryptoprocta (10), Viverra civetta (12, 13), Vlverrlcula malaccensis (15), Genetta (16), Paradoxurus (19, 20), and Herpestes (24). In Proteles (25) it is inserted into the third digit only. Among the Hyaenidae there is no tendon for the aborted pollex; in Hycena striata the muscle went to the third digit only in Meckel's specimen (27), to the second and third in Cuvier and Laurillard's (28), and to the second, third, and fourth in Young's (26). In H. crocuta it went to the second only. The Canidae resemble the Hyaenidae in the feebleness of the slip to the pollex. Out of three specimens of Canis familiaris it went to the first and second in one (37); to the second, with a very feeble slip to the pollex, in another (31); and to the second digit only in a third (39). In C. aureus (41) Macalister found an extensor secundi internodii, but no extensor indicis, while in C. lagopus (42) a Aery feeble extensor indicis alone was present. Among the Ursidae, Windle and Shepherd found no index slip in Ursus americanus (48, 49), but in Cuvier and Laurillard's specimen (52) it went to the pollex and index. In U. arctos (47) and U. marltlmus (45) it had the same insertion. Among the Procyonidae the muscle is more constant; it goes to tbe first and second digits in Procyon lotor (53), P. cancrivorus (57), Nasua (60, 60 a) (in the former (60) the two muscles were quite distinct as far as their origin), and in Cercoleptes (61). In two other specimens of P. lotor (54, 56) the insertion was into the pollex, index, and 1 Sechster Band, V. Abtbeihmg.. 37-39 Lieferung, p 816. |