NOTES ON BATRAOHIANS OF THR PARAGUAYAN CHACO. 311 



vent. In the male this band is bright red. The male is 

 somewhat smaller. The natives call if Po it/' being convinced 

 that the cry which sounds to them thus proceeds from this 

 frog. However, in each case that I tracked down, the frog 

 calling with this cry I found a Leptodactylus ocellatus. 

 The cry was heard everywhere, but I only found one male and 

 one female. 



I think the native boys were here mistaken again ; they 

 pointed out to me holes in the ground beneath fallen tree 

 trunks, of the size of a cricket ball and lined with a froth con- 

 taining white eggs and also tailed larvae. The entrance to the 

 whole was about a centimetre in diameter. This they said was 

 the nest of the '^ Po it." 



I reared some of the eggs, and one as far as the four-legged 

 stage, when the young frog bore a very strong resemblance 



to a Paludicola, but unfortunately escaped from my tank 



before it had lost its tail. 



Though the information obtained from the natives generally 



turned out to be fairly accurate, yet I feel sure that in some 



instances they were quite wrong. 



To whatever frog these nests belonged, it is certain that they 



were a most ingenious contrivance for collecting water and 



keeping the eggs and larvae at least moist, between the storms 



of the wet season. They were always found within the forest 



belts which lay on the highest ground. 



I found with these larvae that they would exist for a verv 



long time in a small quantity of water without increasing in 



size, but that when removed to a tank they grew enormously, 



and very soon left the water. 



These eggs were somewhat larger than the minute eggs of 



Paludicola, 1^ mm., and pigmentless. As far as my investio-a- 



tions have gone these eggs develop much as Paludicola, though 



they are rather more heavily yolked. 



X. Engystoma albopunctatum, Boul. 

 About half the size of E. ovale, and found under a heap of 



