140 PHYSIOLOGICAL SERIES. 



to the inner head of the gastrocnemius, to the plantar fascia. 

 This latter tendinous extension seems to represent the 

 similarly disposed slip of the gastrocnemius of the Monitor. 

 The long tendon of the caudi-femoralis is inserted into the 

 outer head of the gastrocnemius. 0. C. 03 H. 

 Gadow, Morph. Jahrb., Bd. vii. 1882, p. 375. 



C. 181. Portions of tendons from an Ostrich (Struthio camclus), 

 showing two passing through a sheath formed by a third, 

 which, intervening between them and the centre of motion, 

 acts as a patella to them, 0. C. 274. Hunterian. 



C. 182. The parts constituting the tarsal joint of an Ostrich. 

 The flexor tendons of the toes pass through a sheath in 

 the tendo Achillis, which is considerably thickened at 

 that part ; and while it securely retains them in their 

 proper situation, removes them further from the centre 

 of motion at that joint, and augments the lever of the 

 moving power. 0. C. 275. Hunterian. 



C. 183. The tendons and ligaments of the joints of the toes of 

 the Ostrich (Struthio camehis). The sheath of the flexor 

 tendons is of extraordinary thickness behind the metatarso- 

 phalangeal joint. 0, C. 275s. 



C. 184. A vertical section of the tarso-metatarsal bone and 

 phalanges of the greater toe of an Ostrich (Struthio camehis) , 

 and of their flexor tendons. Each bone has its proper tendon 

 inserted into it, which forms a sheath for the tendon of the 

 succeeding phalanx : and on the plantar aspect of each 

 joint is situated a ligamentous substance (analogous to 

 those in the human linger), forming part of that joint, and 

 playing on an articular surface in the lower extremity of 

 the superior bone. These act like patellae, removing the 

 flexor tendons farther from the centres of motion of their 

 respective joints, and forming so many elastic cushions 

 to protect the joints and obviate the effects, by diffusing the 

 forces, of pressure and percussion. 0. C. 276. Hunterian. 



C. 185. Superficial muscles of the right hind limb of a Rook 

 (Trypanocorax frugilegus}. Union between the muscles of 



