1897.] MYOLOGY or THE TERRESTRIAL CARNITORA. 405 



(53, 54, 55) and P. canerivorus (57). lu Nasua (60) it is figured 

 hj Cuvier and Laurillai-d, and, in all these animals, seems to end 

 in the sheaths of the tendons. In Cercohptes (61, 62) it forms the 

 flexor perforatus of the little finger. l]i the Mustelidse it seems 

 to be usually absent, or at all events very feebly marked ; the only 

 record we have of it in this family is in Mustela putorius. 



Palmaris brevis. — The palmaris brevis is apparently never present 

 in Carnivora. 



Thenar Muscles. — This group consists of the abductor, flexor 

 brevis, and opponens of human anatomy. Among the Felidse the 

 only record we have is of the Cat (6), in which the abductor rises 

 from the trapezium and annular ligament ; the usual double- 

 headed flexor brevis is present, and the opponens very small. 

 From our experience of the rest of the muscles of the Felidce we 

 presume that the other animals of the family closely resemble the 

 Cat in their thenar muscles. In the Viverridae, we found a weak 

 abductor and a well-marked flexor brevis in CriJ2^toprocta (10). In 

 Viverra civetta (12) and Yiverneula malaccensis (15) the same 

 muscles were found, though Devis (X.) describes an opponens in 

 addition in Viverra civetta (14). In Paradoxiirus ti/pus (19, 20) 

 and Herpestes rjriseus (24) the abductor and flexor brevis alone 

 were found. 



In Proteles and the HysenidsB there were no thumb-muscles. 

 Among the Canidae we only found two muscles of the thumb in 

 Canis fa miliar is (31), one going to the inner, the other to the outer 

 sesamoid bone (see fig. ]1, p. 406). It is diflicult to determine 

 whether these should be looked upon as two heads of a flexor brevis 

 or as an abductor and adductor. The muscles were small and the 

 nerve-supply somewhat difficult to be quite certain of, but we are of 

 opinion that the radial muscle was supplied by the median, and the 

 ulnar by the ulnar nerve. We are further led to regard the latter 

 muscle as an adductor pollicis by the fact that Cunningham (XLVI.) 

 describes an adductor in the Dingo. The radial of the two muscles 

 rises from the trapezium and is therefore probably an abductor, so 

 that in the Dog a slender abductor pollicis is present, but no oppo- 

 nens or flexor brevis. Among the Ursidte, Kelley (XXIV.) only 

 mentions a flexor brevis pollicis in Ursus maritimus (45). Meckel 

 (XXXIX.) describes the thenar muscles as very strong in U.arctos 

 (47), the abductor in his specimen had two origins, from the 

 trapezium and base of the first metacarpal ; there was in addition a 

 flexor brevis. In U. americanus (49) there were also abductor, flexor 

 brevis, and opponens. Among the Procyonidse, P. lotor (53, 56) 

 has an abductor and flexor brevis, while P. cancrivoms (57) has 

 a small opponens besides. Cercoleptes (61, 62) has an abductor, 

 flexor brevis, and small opponens. Among the Mustelidse, Alix 

 (XXX.) describes a superficial and deep abductor pollicis in 

 M. putorius (65) ; probably these correspond to our abductor and 

 flexor brevis. In M.foina (66) the same two muscles exist, as they 

 do also in Ictonyx (69, 70) and Lutra vulgaris (74). In Lutra 

 cinerea (78) a small opponens was found bj' Macalister. 



