Field Studies of the Non-Social Wasps 463 
moved them one by one, flew high in the air and dropped 
them to the floor, and departed. 
Exp. XXV. At 11 o’clock the spiders were removed 
from a cell that was being filled. The owner brought in 
no more after that, but occasionally she fetched a load of 
mud which she spread over the other portions of the nest, 
until at 3:45 she sealed this cell empty. 
Exp. XXVI. At7 a.m. the two spiders were removed 
from a cell that was being stored; up to 2 o’clock the 
nest remained deserted. 
Exp. XXVII. Eight spiders were taken from a cell 
that was being filled. ‘After that the mother brought 
in mud from time to time and reinforced various por- 
tions of the nest; at noon the cell was sealed, and dur- 
ing the afternoon more plaster was added to the outside. 
CoNCLUSIONS. 
When we attempt, finally, to formulate any generali- 
zations concerning the behavior or psychology of these 
insects, there seems to be only one principle which can 
be relied upon to hold good in all cases, viz., that the 
madam will do as she pleases. Cases of similar conduct 
under homologous circumstances can hardly be found. 
Yet we cannot regard the behavior of the wasp as indif- 
ferent or accidental when we see her very positive air 
in taking action, and her usual determination and per- 
sistence in pursuing it when she has decided upon her 
course of action. 
In most of the cases where the spiders were disturbed 
the owner was quick to detect it and frequently re- 
sented it. But since in her anger she often threw away 
part or all of her own prey, we cannot determine 
whether or not she recognized her own or merely re- 
garded with alarm any meddling about her home. Like- 
