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Show 1876.] OF PASSERINE BIRDS. 511 the humerus a free fasciculus exactly like that above described in the Passeres, except that from about the middle of its lower margin a thin slip runs downwards and wristwards to the fascia of the ulnar side of the outer surface of the forearm. This is represented in Plate L. fig. 1. In the Meropidae, as represented by Merops apiaster and M. ornatus, the only difference from the Galbulidae is that the distal branch is more clearly differentiated, and the slip to the ulnar side of the forearm is nearer the angular bend. This arrangement is represented in Plate XLVIII. fig. 3. In Todus viridis the tendons are similarly disposed. In the Coraciidae. as represented by Coracias garrula and a species of Eurystomus which was not in sufficiently good condition to be more definitely determined, Plate XLIX. fig. 1 represents the distribution of the tendons, there being two parallel to one another, the anterior one of which runs to the superficial ulnar fascia before terminating, and sends wristwards a slip, like that in the Meropidae, to the long; extensor. There is a Passeriform free tendon running back to the lower end of the humerus from the outer tendon. In the Momotidae the condition is the same, except that the outer tendon does not split, and therefore sends forward no wristward slip. This condition I have found in Momotus lessoni, in iii. aquatorialis, and in Eumomota superciliaris. The extension onto the ulnar superficial fascia springs from the portion of the horizontal tendon intermediate between the points of junction of the two parallel long tendons, and is not a direct continuation of either. It is frequently very thin. In the Trogonidae, as exemplified by Trogon mexicana, T. puella, and Pharomacrus mocinno, the condition is very complicated. It is seen in Plate LI. fig. 3. A superficial long muscular mass runs nearly to the long extensor of the forearm. It has a short broad tendinous insertion into the fascia of the outer surface of the forearm ; and this is specially developed in a line running back to the humerus in a Passeriform manner. Deep of this are two parallel tendons: tbe one nearer the humerus terminates exactly like the single one of the Passeres ; that further off ends as in the Pici above described. In the Caprimulgidae, as found in Caprimulgus europaus and Chordeiles texensis tiie arrangement is almost exactly the same as in the Meropidae. The second outer tendon, however, is shorter. In the Macrochires, including the Trochilidae and the Cypselidae, as found in many genera and species the arrangement is uniform. The fleshy belly runs on to a special tendon which springs from the lower end of the outer surface of the humerus (where the horizontal slip in the Passeres terminates), and is continued, parallel to the forearm, along the radial margin to the hand. Plate LI. fig. 1 exhibits this condition. It can be here seen that the tendon of the tensor patagii brevis is not developed, being replaced by the fleshy continuation of the muscle. In Upupa epops the arrangement is fairly simple. The main tendon runs past the free lateral margin of the long extensor to the 34* |