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Show 12 MR. F. E. BEDDARD ON T H E [Jan. 6, is attached to the tendon of the extensor metacarpi radialis longus are prolonged some way beyond that tendon. There is no tendinous slip uniting the distal end of the tendon of the tensor patagii brevis with the tendon of the tensor patagii longus. Neither was there any trace, that I could discover, of a Biceps slip running from the Biceps muscle to the tendon of the tensor patagii longus. The arrangement of these muscles and tendons is not characteristically like that of any of the allied groups ; most of the Gerano-morphae of Prof. Huxley have the Biceps slip, which is, however, absent in Cariamidae and in the Bustards. I may take this opportunity of mentioning that in the Golden Plover (Forbes MS.) the Biceps slip is tendinous, not muscular. Eurypyga helias, generally regarded as a near ally of Rhinochetus, has a large Biceps slip [15] ; I can confirm this by my own dissections. On the other hand, the Herodiones have no Biceps slip, but the arrangement of the tendons of the tensores patagii differs from that of Rhinochetus in the presence of a recurrent slip running from the insertion of the tensor patagii brevis to the middle of the tensor patagii longus tendon. The only birds known to m e with which Rhinochetus can be usefully compared, which have not this recurrent tendon, are the Rails, Eurypyga, and Cariama. (2) The Rhomboideus superficialis is a large fleshy muscle with a tendinous origin for the greater part; it is inserted into the entire length of the scapula, with the exception only of a very small portion at the free extremity, also into the clavicle : this muscle is much thicker anteriorly than posteriorly, but thinnest of all in the middle ; posteriorly its origin is fleshy, but at the end of the second third of the muscle it begins to have a tendinous origin which increases in breadth anteriorly. (3) The Rhomboideus profundus is as usual of much less extent than the rhomboideus superficialis; its origin is tendinous throughout; it is attached along the scapula for about half the length of the bone ; the fibres of the muscle run at an acute angle with those of the rhomboideus superficialis ; at the extremity of the scapula this muscle is not covered by the superficialis. (A) The Latissimus dorsi, as usual, is double ; the anterior section of the muscle (see fig. 2, L.d.l, p. 13) arises from the spine of the last free dorsal vertebra and from the spines of a portion of the succeeding fused mass of vertebrae. It is inserted by a broad fleshy insertion on to the humerus between the biceps and deltoid. The posterior part of the latissimus dorsi (L.d.2) is not continuous at its origin with the anterior; it arises from the spines of the fused set of dorsal vertebrae, from the spine of the following vertebra, and also from the edge of the ilium. Its fibres rapidly converge to a tendon which crosses the anterior muscle, running below it, and is inserted on to the humerus above the insertion of the anterior latissimus dorsi in common with the accessory tendon of the anconaeus longus. (5) The Deltoid (fig. 2, D, D\ p. 13) is largely developed and |