50 PHIL RAU AND NELLIE RAU 



One sees that experience counts for little, that there is no 

 relation 'twixt large nests and learning to fill them properly. 



Spiders that remained uneaten in the cell 



In contrast to the condition mentioned above, there were 

 some cells wherein the insect was past the feeding stage and 

 in the prepupal, pupal or adult condition, and some spiders 

 still remained uneaten. When this occurred, they were counted 

 to see to what extent the mother may give a superfluity of food. 



There were 135 such cells, in contrast to the 176 cells which 

 the mothers had sealed stark empty, and 46 in which she had 

 sealed up the egg with insufficient food. So it seems that the 

 mother wasp is more likely to err by giving her child too little 

 food than by offering too much. The following figures show 

 the number of spiders that remained in each cell after the larva 

 had spun its cocoon. 



The number of spiders that remained untouched varied from 

 1 to 15, the greatest frequency occurring between 1 and 6 spiders. 



Mortality in the larval stage 

 Here we consider the mortality of the organism in the larval 

 stage of growth, due to causes other than starvation. We know 

 this because in every case some uneaten food remained in the 

 cell. The 245 cells, near 6 per cent, of the whole mass, were 

 distributed as follows: 



145 245 



