1905.] AXATOMY OF LIMIOOLINE BIRDS. 163 



other birds on my list the condition is much more complex, bvit 

 as the complexity is similar in all, it is unnecessary to add to the 

 figures given on plate xxi. of Fiii-bringer's great monograph (2). 

 The longus tendon has an anchor to the humerus in all : it is 

 broad and partly doubled in Chionis, Scolopax, VaueUus, and 

 Ilimantopus ; it is single in Glareola, Tkinocorus, Hydropliasianus^ 

 Charadrius, Rhynchcea, and Gcdlinago, 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 hrevis tendon difler, but the details do 

 not apj)ear sufficiently important for individual description. The 

 hrevis 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 hrevis ; its extremity corresponds 

 with y of Fiirbringer and it occasionally turns in towards the elbow, 

 or may ru.n a straight course towards the ulnar margin of the arm. 

 The second division of the hrevis 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 Fiirbringei-, receives the anchor from the longus. 



Pectoralis 2^'i'02Xttagicdis. — -This slip is present in all the birds 

 on my list. Leaving the pectoralis major it joins the deltoides 

 patagialis befoi'e the muscular part of that muscle has given ofi" 

 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 jKttagialis. — 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 Hydropliasianus^ where it is little more than a tendon. In 

 (Edicnemus it sends a- slip to the patagium, recalling the arrange- 

 ment which I have described in Heliornis (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 con- 

 siderable interest. The first salient point is that (Edicnenviis 

 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 Limicolfe recalls the similar 



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