ISELY: EUMENID^ OF KANSAS. 305 



tions — the wasp that had not sufficiently subdued her cater- 

 pillar; the wasp that discarded the earth she excavated and 

 stole fresh earth from the Anthrophora tube to build her own, 

 or the wasp that struggled to carry earth into her nest, in spite 

 of a windstorm that forced the other members of the colony to 

 stop work. In many of the minor activities connected with 

 the nest, the other species, as well as 0. papagorum, showed a 

 wide range of variability. 



Yet these variations are not without a limit. There were 

 in most cases certain habits, typical of a species — just as there 

 are type specimens in structure and coloration for each species 

 — about which the variations centered. As, for instance, while 

 there might be a great difference between the shape of two cells 

 of a species, representing the two extremes in variation; yet 

 the majority of cells would be between the two extremes, and 

 the difference between many of them could be known only by 

 careful and minute measurements. Again, caterpillars in 

 varying states of mobility were stored by individuals of a 

 species; yet this difference in most instances can scarcely be 

 known without a close comparison of individual caterpillars. 

 I know of no mean between the two extreme types of nests of 

 0. dorsalis — the burrow, and the cells above ground; perhaps 

 when our knowledge of this species is more complete this mean 

 will be found. 



In spite of this variability in many habits, there were cer- 

 tain other habits that characterized the family — habits that 

 seemed inflexible and that occurred in all the species observed. 

 There were certain other fixed characteristics that belonged 

 only to a species or to a genus. In the genus Odynerus the 

 wasps do not turn around in the nest ; if a wasp has gone into 

 a nest head foremost it comes out backwards. All that I ob- 

 served used water in nest-building. Members of this genus 

 always take wing after taking out a pellet from a burrow, 

 and drop the pellet while in the air. I have noted no variations 

 from these habits. 



I shall mention some of the habits of the family that are least 

 flexible of those I noted. The food of the wasp grub was 

 always a plant-feeding larva. With no exception, all of the 

 lepidopterous larvse whose envii'onment I observed or that I 

 have read of were spinners. Why such should be preferred I 

 can not imagine. As far as I observed, the caterpillar was 

 always carried in the same way — its head foremost and its 



