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Show 428 MR. F. E. BEDDARD ON THE [June 3, There is only a single patagial muscle, which divides into two tendons, the longus and brevis. The latter, as shown in the drawing (Plate X X X I X . fig. 1), is a single strongish tendon which passes straight to its attachment near to the elbow ; it gives off no recurrent slip to join the longus tendon. As in so many other birds, a muscular slip arises from the biceps and passes into the patagium; it is, however, not attached to the longus tendon, as is so generally the case, but is inserted on to the patagial membrane. I have carefully examined both sides of the body of the single specimen at m y disposal, and have found that the conditions are absolutely identical; it may be therefore reasonably inferred that this peculiar termination of the biceps slip is characteristic of the bird. So far as m y own experience goes, this peculiar arrangement of the muscle is not to be met with in any other Rail-like bird; nor do I find any mention of such by Fiirbringer [4]. In the Colymbiclce, however, in the genera Colymbus, Alca, and Podiceps Fiirbringer figures (4, Taf. xix. figs. 2, 3, 4) and describes a similar ending of this muscle which he terms " Biceps propatagicdisT This is obviously a rather important fact, though perhaps it may be thought that its significance is somewhat reduced by the occurrence of an identical arrangement in the Cormorant; many ornithologists, however, have indicated points of affinity between tbe Steganopodes (particularly Phalacrocorax, Plotus, and Phaethon, see Garrod 3) and the Colymbiclce. Expansor secundariorum.-This is a muscle upon the presence or absence of which Garrod [1] laid very considerable stress as a classificatory mark. I find that it is distinctly present in Podica senegalensis, having an attachment to the teres which is frequently found in other birds. In the Rallidce this peculiar muscle is present, and has the form which Garrod termed Ciconine [lj. In the Colymbidce and Podicipedidce this muscle was " not seen; " however, Fiirbringer found [4] in the latter group undoubted vestiges of the tendon, of which he was unable to trace very definitely the origin or insertion. Merely from the point of view of its presence, then, this muscle does not permit of any conclusions with respect to the relationship of Podica. With regard to the course of the tendon, I have already referred to the fact that it joins the teres at a point wmere that muscle begins to become converted into its tendon of attachment, passing through a fibrous pulley ; the tendon of the expansor secundariorum is here comparatively broad and tough and not easily missed; it then passes beyond the teres and enters the thoracic cavity, ending apparently in the usual way. Anconceus longus.-This muscle (Anc, Plate X X X I X . fig. 4) arises from the scapula by an origin which is fleshy internally, but tendinous externally ; it is also attached to humerus close to its scapular origin ; further down the humerus, a little above the insertion of the latissimus dorsi, is a flat but somewhat narrow tendon (Anc') which attaches the anconceus to that bone. There appear to be no special |