246 THE MYOLOGY OF THE RAVEN. 



is situated posterior to the preceding, and is a long, 

 slender, somewhat flattened, fusiform muscle, whose 

 office it is to assist in flexing the second toe. Laterally 

 its fascia blends, more or less, with the flexors on either 

 side of it ; still, the muscle is well-individualized, and 

 fully entitled to a separate description and name. It 

 arises by a thin and rather broad teudon, in common 

 with the flexor perforatus medius secundus pedis, 

 from the external condyle of the femur. Below, it 

 terminates in a strong though slender tendon, before 

 the last-named muscle does, and passes through the 

 tibial cartilage and hypotarsus of the metatarsus in 

 precisely the same manner, though in each case in a 

 canal deep to it. 



In accompanying the other flexor tendons down the 

 back of the shaft of the tarso-metatarsus, it is found 

 rather to the inner side. Within the region of the 

 sole of the foot it is situated very deep, and just within 

 the accessory metatarsal bone. It finally becomes 

 attached to the sides of the basal joint of the second 

 toe, in the same manner as the other perforated tendons 

 in the other toes, the secundus and deep ones passing 

 through its median bifurcation. 



122. The flexor perforans digitorum profundus 1 is, 

 in point of situation, the deepest of all the flexor 



tare of the feet in Aves very much in the same manner as did the 

 present writer, and his valuable chapter on the subject in the work 

 we have so often quoted in the present volume is well worthy of the 

 closest study and perusal. 



1 We have here a very important muscle of the leg, and one that 

 was thoroughly investigated by Garrod at the time he was in search 

 of structural characters among birds that could efficiently be em- 

 ployed as a means in classification. 



Gadow has collected together the following synonymy for it, and 

 in his work in Bronn's Thier-Reichs gives quite a full resume of the 



