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Show 1896.] ANATOMY OF JECHMOPHORUS MAJOR. 539 the inner tendinous band and the thickened inner strand of the outer band, but above the rest of the tendon. The tensor longus tendon, as usual, dilates at the middle of the patagium into a yellowish thickened nodule of different appearance from the rest of the tendon. From this, or from its immediate neighbourhood, arise a few strands of tendinous tissue arranged in a fan-like fashion, which become collected into a thin tendon running obliquely across the patagium to be inserted on to the tendon of the extensor metacarpi. One of the thin strands which make up the patagial fan is directly continuous with the biceps slip. The muscle in fact appears to end in this tendon, and not to be inserted, as is more usually the case, into the tendon of the tensor longus. The biceps is less fleshy than this muscle often is. The tendons of origin and insertion are continued over the greater part of the muscle as superficial tendinous sheets. The muscle has practically only one head of origin, that from the coracoid ; there is, however, what I believe to be the remains of the humeral head in the shape of an attachment to the under surface of the pectoralis major. The deltoid has an insertion upon the humerus of no great extent. It is attached to that bone for rather less than a third of its length. The anconceus has a humeral head which is a somewhat narrow tendon arising close to the insertion of tbe latissimus dorsi. The expansor secundariorum appeared to be totally absent. The pectoralis major is rather a thin muscle; it is, however, for a portion of its extent divisible into two layers. The superior margin of the muscle, i. e. that furthest away from the carina sterni, is largely tendinous. The insertion of the muscle on to the crest of the humerus is tendinous throughout for about the last eighth of an inch. The pectoralis minor is, as usual, a bipinnate muscle, but the lower side is much wider than the upper. Its origin from the sternum and the carina extends rather more than halfway down. The latissimus dorsi is as usual divided into two muscles, with a branch going to the skin (not always present in birds). This is the dorso-cutaneous of Fiirbringer. The last mentioned overlaps the entire origin of the posterior half of the muscle and is continuous with the origin of the anterior. The glutcsus maximus consists of two separate parts. In front of the acetabulum is a not very wide (£ inch) strap-shaped band about the same size as the sartorius, which it partly overlaps. From the acetabulum to the very end of the ilium arises a sheet of muscle which completely covers the underlying biceps, and is inserted on to the fascia covering the leg from the knee to nearly halfway down. The glutmus medius is incompletely divided into two halves. Ihey run side by side, and are inserted each by a separate tendon ot insertion which are connected by a muscular part. The glutceus minimus is completely hidden by the last muscle; « is small and entirely fleshy and arises from the ilium only. 35* |