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Show 1 9 0 5 . ] ANATOMY OF LIMICOLINE BIRBS. 159 Its insertion is muscular, and just below that of the posterior division (text-fig. 26, L.A. and 3). The posterior division is absent in Scolopax, present in the others, and its proximal edge touches the distal edge of the anterior division in (Edicnemus (text-fig. 26, L.P. and 4) and Hydrophasianus, but not in the others. In Hydro-phasianus and CEdicneinus the two muscles are almost continuous, although they cross before insertion, at which point they are closely in contact; whilst in the others the tendon of the posterior division is separated by a short gap from the muscular and more distal insertion to the humerus of the anterior division ; this tendon is always in close association with the humeral anchor of the anconseus. Text-fig. 26. Shoulder-muscles of (Edicnemus scolopax. Left shoulder; external view. 2. Tendon of supra-coracoideus. A.S. Anconseus scapularis, the reference lines pointing respectively to the humeral origin and the scapular anchor. S A . Scapuli-humeralis anterior. S.P. Seapuli-humeralis posterior. S. Expansor secundariorum. L.A. Latissimus dorsi anterior. L.P. Latissimus dorsi posterior. 3. Insertion of lat. dors. ant. 4. Common insertion of lat. dors, post, and humeral anchor of ancon, scapularis. The posterior division, where present, tends to spread backwards to reach the ilium and part of the ribs. In Chionis its origin is limited to the vertical anterior edge of the ilium, whilst the gap between it and the anterior muscle is wider than in any of the other birds. The archecentric, or most generalised, condition of these muscles in Birds appears to be the existence of an anterior and posterior division, fairly well separated at their origins and close together |