Occasional Papers of the Mnsciini of Zoology 5 



when his figures are examined. Drawings B, C, E, F, Figure 

 I, indicate a reduction in the extensions of the terminal phal- 

 anges of lincatiis with age; but if the phalange reproduced in 

 drawing A is, as stated in the legend, that of an adult specimen 

 of this species the reduction with age cannot be without excep- 

 tions. Ignoring drawing A and granting a reduction with age 

 Noble has not shown that the simple condition found in adult 

 Leptodactylids is reached, the adulj; condition in L. lincatus be- 

 ing comparable to the immature condition in Leptodactylids as 

 far as shown by his figures. 



The writer has examined the phalanges in a series of speci- 

 mens of Lcptodactylus albilahris and finds a change in pha- 

 lange form in this species of Lcptodactylus such as Noble de- 

 scribes for L. niclanonotns: the phalanges are T-shaped, the 

 dilations being blunt in the young and only swollen on the 

 end in the adults. Also in two specimens of lincaius, a part- 

 ially grown individual and an adult, the phalanges are striking- 

 ly T-shaped in the young, the expansions being long and atten- 

 uated toward the ends, and short and blunt in the adult; in 

 other words, the development is as represented by Noble's 

 figures C and F. It is clear that if the adult form of the pha- 

 lange in the specimens of lincatus now at hand is described 

 as simple, that of the young of Leptodactylus species cannot be 

 called T-shaped, for the change which takes place in the life- 

 history of lincatus stops where the similar change, in the on- 

 togeny of the Leptodactylus species begins. Quite obviously 

 this does not establish the generic identity of lincatus and the 

 species hitherto referred to Leptodactylus, and it seems advis- 

 able to consider the former as generically distinct, — at least 

 until it is shown that there are species which have the characters 

 of Leptodactylus and an ontogenetic change in phalange form 

 from a distinctly T-shaped to the simple type. If lincatus is re- 



