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Show 1890.] HELODERMA SUSPECTUM. 169 (1) Its first head, and distinctly the largest, arises from the entire posterior aspect of the shaft of the humerus, from the head of the bone to the condyles. This part of the origin of the triceps is comparatively carneous. (2) Another, and a very much smaller, carneous head springs from a longitudinal line upon the posterior aspect of the shaft of the humerus, extending from the tuberosity to a point a little above the internal condyle. At the upper part of the shaft of the humerus the insertional tendon of the latissimus dorsi passes between these two heads. (3) A strong, cord-like tendon of the triceps springs from the superior glenoid margin of the scapula, which merges into the fleshy part of the muscle after it passes the head of the humerus. W e find given off from the proximal end of this tendon, a thin, though strong tendinous sheet, which passes across to the humeral head, binding down as it does so the insertional extremity of the teres minor. (4) Finally, we find a long flat tendon of the triceps arising from the inner surface of the coracoid near its postero-inferior angle. This crosses over to the upper part of the belly of the muscle, and merges into it at a point immediately in front of the insertion of the latissimus dorsi. A tendinous connection is made between this last-named muscle and this coracoid-head of the triceps at the point we have indicated. The triceps is inserted by a powerful tendon into the olecranon process of the ulna, but no sesamoid develops therein as was found to be the case in Parson's Chamseleon by Mivart, aud in Liolepis belli by Sanders. This sesamoid is also alluded to by Hoffmann as the " patella ulnaris," in Bronn's ' Thier-Reichs ' (loc. cit. p. 632). Of the Musculature of the Antibrachium and Manus. 36. Supinator longus.-This, one of the most important aud conspicuous muscles of the forearm, arises semitendinous from the external condyle of the humerus, aud immediately makes insertion along the entire length of the shaft of the radius, upon its supero-external aspect. Hoffmann has very truly remarked in reference to this muscle that " M a n kann an diesem Muskel gewbhnlich zwei zuweilen drei oder selbst vier Portionen unterscheiden (letzteres bei Lguana, nach Mivart). Alle diese Portionen entspringen von dem Epicondylus s. Condylus externus humeri (bei Platydactylus auch noch von dem unteren Drittel des Humerus, bei Liolepis oberhalb des Condylus). Seine Insertion findet, wie gesagt, an der ganzen Lange des Radius statt." These remarks apply equally well to the supinator in Heloderma. 37. Extensor digitorum longus.-In this we have another muscle which is prominently developed in the forearm of our present subject. Arising by a strong tendon from the external condyle it passes down the limb to merge into a thin, flat tendon over the wrist-joint, beyond which it trifurcates, a slip going to be inserted |