AN ISLAND SETTLEMENT. 67 



were whole quivered the legs on provocation. Larva was 1-3 of an 

 inch long-. The flies consisted of one small Asilid, one Syrphus, and 

 one Blue-bottle, with three or four other partially destroyed and 

 smaller species." 



Twice we have seen our spinolae, as she was bringing home 

 her prey, alight near the nest and sting it as it was held with 

 the second pair of legs. We could see the process distinctly since 

 she is slow and clumsy, and, in one instance, had difficulty in 

 reaching the fly, falling over to one side in an awkward manner. 

 It is probable, then, that this is a habit with the wasp, but that 

 the sting is usually given at the place of capture. 



Fabre explains the habits of Bembcx in regard to feeding her 

 young by the nature of her prey. Diptera must be seized while 

 in rapid motion therefore they are likely to be crushed and 

 killed as there is no time for nicety of handling. They contain, 

 relatively, but a small amount of moisture therefore they can- 

 not resist desiccation and would become unfit for food if they 

 were stored up in numbers to last through the period of larval 

 life. 



This seems reasonable, although we know that Beiribex can, 

 since she often does, catch her flies so delicately that not a hair 

 is injured. As to the rapidity of desiccation, this would 

 scarcely hold true, for the crickets used by Lyroda in feeding 

 her young from day to day, and at any rate, some of the big, 

 soft-bodied flies that are taken by Bembex are quite as juicy as 

 the Gastera^anthidae, beloved ofPelopaeus fistularis* or as 

 some of the beetles taken by Cerceris. Be that as it may, wa 

 have another suggestion to offer. 



May it not be that instead of having departed from the or- 

 dinary habits of the solitary wasps, Benibex, in its relations to 

 the larva, represents the original or least modified form of all 

 the wasps? In their semi-social habits the wasps of this genus 

 seem to show a stage in the transition from the earlier state of 

 the truly solitary species toward the more complex and higher 

 relations existing among those that live in communities. The 



*Bates, Naturalist on the Amazon, p. 186. 



