74 INSTINCTIVE BEHAVIOUR 
and delicate instinctive behaviour is in direct relation to the 
uniform result of prolonged paralysis and consequent preserva- 
tion of the food in the fresh state. But Dr. Peckham’s careful 
observations and experiments show that, with the American 
wasps, the victims stored in the nests are quite as often dead 
as alive ; that those which are only paralyzed live for a vary- 
ing number of days, some more, some less ; that wasp larve 
thrive just as well on dead victims, sometimes dried-up, some- 
times undergoing decomposition, as on living and paralyzed 
prey; that the nerve-centres are not stung with the supposed 
uniformity ; and that in some cases paralysis, in others death, 
follows when the victims are stung in parts far removed from 
any nerve-centre. “ We believe,” he says, “that the primary 
purpose of the stinging is to overcome resistance, and to pre- 
vent the escape of the victims, and that incidentally some of 
them are killed and others are paralyzed.” 
If, therefore, as will probably be shown to be the case, 
these conclusions are found to be generally true for this in- 
teresting group of insects, the mystery of “the precise ana- 
tomical, not to say also physiological knowledge which appears 
to be displayed” by these wasps turns out to be one of our 
own fabrication. It melts away in the light of fuller and 
more searching investigation. 
It must not be supposed, however, from what has been 
said, that the behaviour in the act of stinging is altogether 
indefinite. On the contrary, each species proceeds in a rela- 
tively definite manner with some variation or modification of 
method. Philanthus punctatus, for example, stings the bees, 
on which she preys, under the neck, and the thrust is at once 
fatal. Dr. Peckham further notes that he was only suc- 
cessful in getting the wasps to sting when they were hunting ; 
those that had not yet begun to store the nests paid no 
attention to the bees. This is an example of that internal 
factor to which reference was made in the last section. 
Marchal observed that Cerceris ornata runs the end of her 
abdomen along the under surface of the thorax of the bee, and 
delivers her thrust at the division of the segments—that is, 
