258 
Psyche 
[September 
In order to eliminate possible additional variables, only one species 
of cricket, Gryllulus domesticus L. has been used. Liris nigra 
generally succeeds in paralyzing immatures only. Adults, although 
attacked, are apparently too large for this species of wasp. 
This paper represents observations made during detailed study of 
paralyzing behavior of the wasp. Several aspects of the wasp-cricket 
interaction are developed more fully than in previous publications 
(Steiner, 1962). 
Common behavioral responses in usual hunting conditions: 
MAIN CHARACTERISTICS 
It is convenient to subdivide the hunting phase of the nesting cycle 
into two periods, termed “early” (Plate 21) and “full” (Plates 22 
and 23) hunting phases. No clear cut line separates these periods. 
The most typical characteristics of each are given in Table 1. 
The hunting phase provides an overall graded scale of increasing 
intensities and degrees of completeness from onset to completion. 
This hunting phase is used here as a framework for studying the 
responses of the prey and especially the intensity-dependent aspects of 
these responses. 
Except for the hunting phase of the typical nesting cycle, crickets 
and Liris typically seem to ignore each other. However, a wasp 
occasionally pounces on a cricket at other times and even paralyzes 
it. This can be observed at early stages of the daily cycle of activi- 
ties before the wasp is engaged in the nesting cycle and rarely even 
outside the nesting season itself. Malaxation generally follows this 
and then the cricket is abandoned. 
Interactions of wasps and crickets consistently change throughout 
the hunting phase like many other parameters described in Table 1. 
Interactions and responses typical of early hunting phase 
(Represented on Plate 21) 
These interactions become more frequent, vigorous and complete 
from onset to peak of the hunting phase. Increase in vigor of the 
interaction (parameters 5 of Table 1) is indicated by an increase in 
the number of arrows on the path followed by the wasp. The line 
representing this path is more direct and less frequently interrupted 
from a to f. It indicates that the displacements of the wasp become 
more direct and selective (parameter 3 of Table 1) and less fre- 
quently interrupted by non-hunting activities or rest (parameter 4 
of Table 1). 
For simplification, crickets are supposed to be motionless and at 
rest before the interaction (Figure O, Plate 21). 
