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Show 8 Q MR. A. SANDERS ON THE [Jan. 6, sented ; in L. belli the longus only occurred ; but neither were found m kiTcarpiulnaris arises by two heads-one from the i^er condyle in conjunction with the extensor digitorum perforans, the other from the proximal end of the ulna; this part is in intimate connexion with the extensor carpi ulnaris; the whole is inserted into the pisiform bone and into the flexor surface of the base of the metacarpal bone of the fifth digit. ., . „„„ Flexor carpi radialis (fig. 1, F.C.R.) arises from the inne. condyles, also in conjunction with the flexor perforans, andlis inserted into the radial side of the first digit, being closely attached to the scaphoid in its passage across the carpus. Flexor perforatus digitorum arises, as usual, from a tendinous band across the wrist; it gives off a slip for each digit, the tendons dividing for the passage of the perforans. Flexor perforans digitorum arises from the internal condyle and from about two thirds of the proximal end of the ulna; it forms a broad tendinous expansion in the palm, which receives a muscular slip from the ulnar side of the carpus, and then divides into live tendons, one for each digit. The superficial muscle on the ventral aspect of the thigh does not extend so forward as the one in L. belli or P. japonicum; I therefore conclude that the first muscle in those species, viz. the sartonus, is absent from P. coronatum, and that the muscle met with immediately beneath the skin represents the more posterior and deeper muscle, viz. the . Gracilis (figs. 4 & 6, G.), which arises from a small portion ot the posterior end of the ischio-pubic ligament*, from the pubic symphysis by means of a thin aponeurosis, and from the ventral angle of the ischium; it becomes more contracted in descending the thigh, and is inserted by a narrow tendon on the inner surface of the tibia not far distad of the knee-joint. Transversus perinei (fig. 4, Tr. P.) is well marked in this specimen ; it arises as in L. belli, from the cartilaginous rod which is the continuation backward of the ischio-pubic symphysis, and, forming a broad plane of muscular fibre, is inserted into the ilio-ischiatic ligament, or that ligament which extends from the ischium on the ventral surface to the posterior point of the ilium dorsad. This muscle is placed in front of the cloacal aperture; it appears to correspond to the transversus perinei in Iguana, but not to the muscle described under the same name in Chamaleon. Behind it are several small muscles devoted to the office of opening or closing this orifice ; of these the Dilatator cloaca (fig. 4, D.C.) arises from the connective tissue beneath the hypapophyses of the 5th and 6th caudal vertebrae ; and passing forward in the central line, it divides into two branches, like the letter Y> which are inserted, one on each side of the cloacal aperture, into the connective tissue of its posterior lip. * Which is the tendinous band extending from the hanmlar process of the pubis to the ischium. |