372 



( 



pad is more normal in proportion. The fourth interdigital 

 pad is displaced considerably proximally and towards the 

 ulnar side. The hypothenar pad is well developed. 

 ,^^ Pes. — The digital formula for the pes is 4;>5;> 

 2.3>1 (see figs. 11 and 12). The early specialization 

 of the first digit is remarkable, as is also the high degree of 

 development of the syndactylous elements. Claws are devel- 

 oped upon digits 2.3, 4, and 5; but, as John Hunter noted, 

 no claw is present on digit 1. At no stage have I been able 

 to detect any naked eye appearance of a nail or claw on this 



\ 



) 





Fig. 13. 



External genitalia of the male (from Speci- 

 men male A, Perth Museum). 

 S, scrotum. GT, genital tubercle. CM, 

 cloaoal margin. 32 mm. stage. 



Fig. 14. 



External genitalia of the male 



(from Specimen male C, 



Piper). 



S, scrotum. GT, genital 



tubercle. CM, cloacal margin. 



65 mm. stage. 



highly-specialized digit, which in the earlier stages stands in 

 marked opposition to the rest of the digits. 



It is noteworthy that the syndactylous toilet digits 2 and 

 3 are early and progressively specialized, and that the webbing 

 between 3 and 4 becomes more marked with increasing 

 development. Apical pads are well developed. Interdigital 

 pad 1 and the thenar pad are fused. Interdigital pads 2, 3, and 



