OCR Text |
Show 472 MR. W. A. FORBES ON L E P T O S O M A DISCOLOR. [June 15, diagrammatically represented in fig. 3 ; as will there be seen, the tendon of the flexor longus hallucis (f.l.h.) joins the tendon of the flexor profundus digitorum (/.p.di) on the outer side, some little way above the phalanges, and completely blends with it. From the single compound tendon so formed the small slip to the hallux is given off, on the inner side, just before the common tendon splits up for distribution to the three other digits. This is exactly the same condition as that found by Prof. Garrod in Coracias garrula, and by myself in Atelornis crossleyi (in a skin). It differs completely from that found in the Psittacidae, Cuculidae, and Musophagidae on the one hand, and that of the Galbulidae, Bucconidae, and Picidae and their allies on the other. Therefore this fact, when taken in conjunction with the statements already made as Fig. 3. fr&\ f.ih TV HI Diagram of the arrangement of the deep plantar tendons in Leptosoma. f I. h., the flexor longus hallucis; f.p. d., the flexor profundus digitorum. to the natural position of the fourth digit in Leptosoma, shows there are no real grounds for calling Leptosoma a " zygodactyle" bird l. As regards other points, it may be mentioned that the vessels and nerves of the thigh are normal; that is to say, the sciatic nerve and artery and the femoral vein are all present in their normal position. There are two carotid arteries present, both of them being unusually small, the left particularly so. They run up in the usual converging way, springing from the vertebral arteries into the hypa-pophysial canal of the neck, and there become so closely applied to each other that it is impossible to dissect them away as "can usually 1 In Podargus cuvieri, where the outer toe is reversed in perching, and in Colius, where the toes are directed at various times in very different ways, the " same blended" distribution of the deep plantar tendons obtains. |