234 THE MYOLOGY OF THE RAVEN. 



Some ten years ago the late Professor Garrod con- 

 tributed to the Proceedings of the Zoological Society 

 a paper setting forth some of his very important and 

 interesting investigations upon the deep plantar tendons 

 in different birds. 



He shows that there was considerable diversity among 

 these tendons in the class, both in their behaviour in the 

 sole of the foot, as well as at the back of the tarso- 

 metatarsus. 



The tendons of the flexor perforans digitorum, and 

 the present one, sometimes cross each other in certain 

 birds in a peculiar though constant way; at others, 

 these two tendons are united by a descending fibrous 

 vinculum. "In all cases this vinculum is always 

 directed downwards from the hallux muscle to the 

 digits muscle, so that, when the tendon of the flexor 

 perforans digitorum alone is pulled upon, the three 



is overlapped by the more superficial flexors, while in turn it has 

 beneath it the flexor perforans diyitorum profundus. About half- 

 way down the leg it gives way to a strong tendon, which, passing 

 deep in the tibial cartilage, crosses the ankle-joint to pass through 

 the outer canal of the osseous portion of the hypotarsus of the tarso- 

 metatarsus. Down the back of the shaft of this latter bone the 

 tendon exhibits a disposition to develop an osseous rod in its con- 

 tinuity, but this does not actually occur in my specimen. It lies in 

 this region just above the tendon of the deep flexor, and, immediately 

 above the sole, makes a fibrous connection with it of some extent. 

 This fibrous ' vinculum ' is in no way oblique as it is described by 

 Garrod for many birds, but passes directly from one tendon to the 

 other for about eight millimetres, and were it not known that it as 

 a rule passes obliquelyyVom the flexor longus hallucis, it would be 

 quite impossible here to designate which tendon was responsible for 

 the connection. 



" In the foot the long tendon of the hallux passes in the usual 

 way to become inserted on the tubercle at the under side of the 

 proximal end of the lingual phalanx." (See 120 of Bibliography at 

 the end of this volume.) 



