4 Some Solitary Wasps of Texas. 



The solitary wasps mate in the spring or summer. The female 

 alone engages in the work of rearing the family. When the egg- 

 laying time arrives, she digs or builds a nest, secures her prey, which 

 she either kills outright or merely paralyzes, stores it in her nest 

 and lays her eggs among the store of provisions. In most cases, 

 the food is carried home once for all, the nest is closed over the egg 

 and the mother flies away and digs a nest in another place, paying 

 no further attention to the old nest. In a few genera, the mother 

 maintains a further connection v/ith her offspring, feeding the 

 growing larva from day to day until it has spun its cocoon. 



The egg of a solitary wasp hatches in one to three days into a 

 maggot-like larva, which feeds on its store of provisions and grows 

 for two weeks or less, Avhen it spins its cocoon and becomes a pupa. 

 In this state it remains two or three weeks in summer before 

 emerging as the perfect insect; or if cold weather comes on, the 

 insect remains quiescent in the pupal state until the following 

 spring. It is probable that no adult solitary wasp survives the 

 winter. 



The solitary wasp emerges from its cocoon in possession of all 

 the instincts of its ancestors. It is, moreover, born into the world 

 alone, and there is no chance for imitation of its fellows, as is the 

 case with social bees and wasps. Wonderful as these instincts are, 

 they are not so perfect as was supposed, for observation has shown 

 that they are to a high degree variable, and often show remarkable 

 adaptation to circumstances, which is called by some, intelligence. 

 The study of the habits of animals had been too little studied to 

 bring out the fact of variabilit}^, for it is apparent that, to detect 

 variations, be they in morphological characters or in actions, the 

 type of structure or the normal action of the animals must first 

 be determined. The present paper is a contribution in this direc- 

 tion, as it embodies observations of some twenty-eight species of 

 Texas solitary wasps. 



The principal students of the habits of solitary wasps, in fact, 

 the only ones that have studied them comparatively, are M. J. H. 

 Fabre of France and Mr. G. W. and Mrs. E. G. Peckham of Mil- 

 waukee, Wis. M. Fabre has given us the results of his keen and 

 careful observations in his interesting and delightful papers, "Souve- 

 nirs Entomologiques." The Peckhams published their equally in- 

 teresting results with sound deductions on the instincts of animals 

 in "Observations on the Instincts and Habits of Solitary Wasps", 

 Bulletin No. 2, Wisconsin Geological and Natural History Survey, 



