472 



MR. W. A. FORBKS ON LEPTOSOMA DISCOLOR. [June 15, 



diagrammatically represented in fig. 3 ; as will there be seen, the 

 tendon of the Jlexor longus hallucis {f.l.h.) joins the tendon of the 

 flexor profundus digitorum {f.p.d.) 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 oif, 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 crosslexji (in a skin). 



It differs completely from that found in thS Psittacidse, Cuculidse, 

 and Musophagidse on the one hand, and that of the Galbulidae, Buc- 

 conidae, and Picidae and their allies on the other. Therefore this 

 fact, when taken in conjunction with the statements already made as 



Fig. 3. 



^pd 



Mh 



W M 



Diagram of the arraugement of the deep plantar tendons in Lepfosoma. 

 f. l.h., the flexor longus hallucis; f.p.d., ^e flexor profundus digitorum. 



to the natural position of the fourth digit in Leptosoma, shows that 

 there are no real grounds for calling Leptosoma a " zygodactyle" 

 bird '. 



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 un- 

 usually 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. 



