176 



PROF. G. B. HOWES AND \V. RIDEWOOD ON [Mar. 6, 



becomes modified preaxially in connection with the thumb-pad. 

 We have nothing to add to Leydig's account of this feature (2(i). 

 The heads of the 2nd, 3rd, and 4th metacarpals are expanded and 

 more or less considerably excavated, for articulation upon the carpalia 

 and the capitato-hamatum. The head of the .5th metacarpal is, lilce 

 its shaft, comparatively very slender, vyhile it is so modified as to 

 embrace the postero-external angle of the capitato-hamatum in the 

 manner of a pincers apparatus. 



Hind Foot (Rana temporaria). 



The astragalus and calcaneus (a., c.) are much elongatel, confluent 

 at their extremities, concave internally, and either circular or elliptical 

 in section. Their internal borders l)ound the limits of origin of the 

 adductor longus digiti primi muscle, the tendon of which {m.a.l.) 



Fig. C. 



joTi. ii 



pll.i 



Bana temporaria, J, 54 mm. in length. 



Left bind foot, dorsal view, x 12. m.a.l. tendon of the adductor longus 

 digiti primi muscle. Other references as at p. 182. 



is inserted into the naviculai-e {n). With the full development of this 

 there arises from the epiphysial cartilage of the astragahis a 

 prominence which overlies the tendon ', and which ossifies with age ; 

 in okl individuals there passes between it and the calcaneus an 

 annular ligament. 



Tarsalia 4 and 5. — Represented in ligament, which is not recog- 

 nizable in adult specimens. 



Taisalia 2 and 3. — Invariably united to form the splint-like 



^ Cf. Ecker (17, p. 128, and fig. 91). 



