496 Saw-flies, Gall-flies, Ichneumons, 



three times, once in each thoracic ganglion, which resulted in immediate 

 complete paralysis. Cerceris tuberculata hunts weevils (Cleonus) (Fig. 698) 

 and stings them exactly in the large central ganglion formed by the fusion 

 of the three thoracic ganglia, paralyzing them immediately. Insects thus 

 paralyzed will keep alive, flexible, and fresh, but immovable, as Fabre has 

 observed, for six weeks, a much longer time than is necessary for the develop- 

 ment of any of the wasp larvae. The amazing expertness and accuracy 

 displayed in plunging the sting into exactly those spots where injury will 

 give rise to exactly that physiological phenomenon in the prey that will make 

 it available for the special conditions attending the wasp larva's sustenance 

 this adroitness and this seeming knowledge of the structure and the 

 physiology of the prey have led some entomologists to credit the solitary 

 wasp with anthropomorphic qualities that are quite unwarranted. The 

 whole behavior is probably explicable as a complex and advantageous reflex 

 or instinct, developed by selection. 



Similarly the whole course of the nest-building and provisioning is an 

 elaborate performance wholly for the sake of the young which the mother 

 will likely never see; and these young in turn will if females do the same thing, 

 perfectly and in essentially if not exactly the same manner without ever 

 previously seeing such remarkable processes performed. All these com- 

 plex and altruistic habits have naturally led to much speculation concern- 

 ing their origin and their relation to psychical conditions. Whether a con- 

 sciousness of what is being done and an intelligence is brought to bear upon 

 its doing; whether we may attribute to the wasp a psychical state, with its 

 attributes of cognizance, reason, and emotion these are questions which 

 are debated warmly. The consensus of opinion, however, is distinctly 

 adverse to the reading into the behavior of Ammophila or any of its allies 

 anthropormorphic attributes of reason, consciousness, and emotion. 



The fixity and inevitableness which is, despite the slight variations of 

 practice noted by the Peckhams,* pre-eminently characteristic of the behavior 

 of the wasps, and the fact that each female is ab ovo adequate to carry through 

 the complex train of actions without teaching, experience, or opportunity 

 for imitation, practically prove all this seeming marvel of reasoned care for 

 the future young to be an inherited instinct incapable of essential modification 

 except by the slow process of selection through successive generations. 



Nevertheless, as Sharp well says, the great variety in the habits of the 

 species, the extreme industry, skill, and self-denial they display in carrying 

 out their voluntary labors, render the solitary wasps one of the most instruc- 

 tive groups of the animal kingdom "The individuals of one generation 



* Peckham, Geo. W. and Eliz G., On the Instincts and Habits of the Solitary Wasps, 

 Bull. 2, Wis. Geol. and Nat. Hist. Survey, 1898. 



