504 PROF. HOWES AND MR. A. M. DAVIES ON THE [DeC, 4, 



stand alone among Anura in the life-long retention of the inter- 

 phalangeal syndesmoses. 



/. PeLOBATIDjE. 



Examined : — 



Pelodytes punctatus, 39 millim. 

 Xenophrys monticola, 48-5 millim. 



In Xenophrys the syndesmoses are feebly represented. That of 

 the terminal joint is complete and Tentrally enlarged, but reduced 

 and feebly hgamentous in its middle. The fibres of the latter por- 

 tion (/., fig. 8) pass from the distal face of the penultimate phalanx 

 obliquely upwards and forwards, to be inserted into the proximal 

 face of the terminal one. It will be obvious that there is here an 

 approximation towards the condition of the inter-articular ligament 

 of the RunidcB and Hylidce; and this species is particularly interest- 

 ing as showing that there is no leading modification undergone by 

 the proximal syndesmoses for which a counterpart cannot be found 

 in the terminal one. 



The syndesmoses of the proximal joints are annular and largely 

 absorbed, exhibiting traces of the inter-articular ligament of the 

 above-named families. 



Pelodytes, the affinities of which with this family have been 

 called into question \ while most nearly Pelobatoid, shows, with 

 respect to its proximal syndesmoses, a tendency towards a condition 

 intermediate between the Pelobatidce and Discoglossidce ; for these, 

 while more independant of the apposed surfaces of the phalanges 

 than in the Discoglossidse, are still imj>erforate. 



B. AGLOSSA. 



Examined : — 



Pipa americana, adult c? . 

 Xenopus Icevis, adult $ . 

 The terminal joint of the hind limb was alone examined in each 

 case. It was found to consist, in both genera, of a coarsely filjrous 

 syndesmosis, showing no trace of special diiferentiation and most 

 nearly suggestive of the condition seen in Pelodytes. 



C. URODELA. 



Examined : — 



MoJge cristata, 135 rnillim. 



M. pahnata (larvae), 25 millim. 



M. wnltlii, 175 milhni. 



Proteus angidnus, 135 and 220 millim. 



Salamandra atra, 130 millim. 



S. maculosa, 140 millim. 



Spelerjies fusca, 130 millim. 



In this Order the syndesmoses are throughout uniform in structure ; 



1 Cf. this vol. p. 125. 



