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Show 1 9 0 5 . ] ANATOMY OF LIMICOLINE BIRDS. 1 6 3 other birds on my list the condition is much more complex, but as the complexity is similar in all, it is unnecessary to add to the figures given on plate xxi. of Fiirbringer's great monograph (2). The long us tendon has an anchor to the humerus in all: it is broad and partly doubled in Chionis, Scolopax, Vanellus, and Himantopus; it is single in Glareola, Thinocorus, Hydrophasianus, Charadrius, Rhynchcea, and Gallinago, although in these a greater width in the elastic portion shows a tendency to duplication. In all, from just below the middle of its course, it sends a tendinous anchor inwards and downwards to join with the a portion of the brevis tendon ; the width of this anchor and the exact point and mode of junction with the brevis tendon differ, but the details do not appear sufficiently important for individual description. The brevis tendon is doubled in all, the duplication being complete from origin to insertion. A well-defined tendon nearest to the biceps runs towards the elbow, where it is practically free from the second portion of the brevis; its extremity corresponds with y of Fiirbringer and it occasionally turns in towards the elbow, or may run a straight course towards the ulnar margin of the arm. The second division of the brevis is stronger and wider; it runs parallel with the latter, and nearer the longus tendon. At its distal extremity it divides into two well-marked slips-the proximal, being the /3 of Fiirbringer and spreading out into a fan running towards the ulnar margin of the arm, whilst the more distal, the a of Fiirbringer, receives the anchor from the longus. Pectoralis propatagialis.-This slip is present in all the birds on my list. Leaving the pectoralis major it joins the deltoicles patagialis before the muscular part of that muscle has given off the longus and brevis tendons, but its fibres run towards the longus rather than to the brevis. It is weakest in Glareola and Thinocorus. Biceps patagicdis.-This muscular slip, to the presence or absence of which Grarrod attached so much importance, is present in all these birds and joins the longus. It is much weaker in Glareola and Hydrophasianus, where it is little more than a tendon. In (Eclicnemus it sends a slip to the patagium, recalling the arrangement which I have described in Ileliornis (7, text-fig. 78, p. 640). Its length varies, it being much longest in Himantopus, where its distal end nearly reaches the radial margin of the arm-an extremely specialised condition. Where the biceps is double, the origin of the biceps patagialis is sometimes from both portions (text-fig. 27, BI. P. p. 161), but in other cases it comes from the acro-coracoid head only, and in others again from the humeral head. The condition of these alar muscles and tendons is of considerable interest. The first salient point is that (EcMcnemus stands markedly apart from the others, showing in these structures, as in the biceps, an arrangement much more resembling that found in the Gruiformes, and, indeed, in many other birds, than the typical Limicoline condition. On the other hand, just as the complexity of the biceps in the Limicoke recalls the similar 11* |