292 Proceedings of the Royal Society of Victoria. 



tasmaniensis from Victoria, and Limnodynastes ornatus and 

 Chiroleptes platycephalus from Central Australia, for specimens of 

 which, together with those of Hyla aurea, I am indebted to 

 Professor Spencer. There being but few observations in each 

 case, I have not attempted to tabulate the results, as a few 

 words with a reference to the figures and tables of Hyla aurea 

 will make their size, condition, etc., clear, since here I have 

 taken the same standards for comparison. The manner of 

 distribution and position of the various nerves do not differ very 

 greatly from those of Hyla aurea. 



In Helioporus pidus the various thicknesses found are the 

 following : — 



Nerve. Thickness. Percent. 



II. - 4 - 50 



III. - 5 - 50 



IV. - 6 - 50 



V. - 2 50 



VI. - 3 - 50 



VII. - 2 - 50 



VIII. 3 50 



IX. 7 50 



X. - 7 50 

 XL 1 50 



Nerve XII. was not found to occur at all. 



The following conditions were observed in the nerves of 

 Heliopot us pidus. 



We find Fig. 1, form ii., with nerve VIII., thickness 2, and 

 Fig. 1, form iii., with nerve VIII., thickness 3, showing with an 

 increase in thickness of nerve VIII. a corresponding advance in 

 the composition of the ileo-hypogastric nerve comparable to that 

 of Hyla aurea. 



In the cruralis we have Fig. 2, form v., occurring with nerve 

 VIII., thickness 2, and nerve IX., thickness 5, and form vii., 

 with nerve VIII., thickness 3, and nerve IX., thickness 7. 

 Thus we see that both the ileo-hypogastric and cruralis show 

 here as in Hyla aurea a forward Homuiosis in the origin of these 

 two nerves, viz., from nerve IX. to nerve VIII. , the ileo-hypo- 



