2i6 The Ottawa Naturalist. [January 



insects, which vary in kind according to the wasps collecting 

 them. Any observant person may, during the summer months, 

 watch the agile mother-wasp hunting for its special prey, which 

 when captured is paralyzed by the potent venom injected by the 

 captor's sting. Thus the grubs, when they hatch, have fresh meat 

 provided for their voracious appetites, and at the same time are 

 secure from injury by their victims. They are not, however, in 

 all instances exempt from parasitic species, which find access to the 

 cells during the course of construction and deposit eggs, from 

 which larvae hatch and proceed to consume the food so industriously 

 stored, and either devour or starve, the rightful occupants. 



The superfamily is divided into twelve families of which all 

 but the Stizidae (which includes the great cicada-hunters) and the 

 Ampulicidas (rare cockroach-catchers) have representatives in our 

 district. The family Oxybelid^ furnishes two small species, of 

 which the commoner one was found by the Peckhams to store 

 with flies its burrows in the sand. The family Crabronidae con- 

 tains one-third of all our species, usually in livery of black and 

 yellow. 1 hey may often be seen about old stumps and trees, 

 disappearing in burrows made either by themselves or by some 

 departed beetle. The food collected varies with the species. The 

 PemphredonidcC are rather small and generally black and their 

 habits are much the same as those of the crabronids. Of the 

 Bembicidse wehaveonlythreespecies, of which two are common and 

 are easily known by the long beak-like labrum. They are strong 

 active insects frequenting sandy fields in which their burrows are 

 stored probably with diptera. The Larridae are more numerous 

 and are more bee-like in form and in color black, with sometimes 

 a red band on abdomen. In their burrows they store small grass- 

 hoppers, etc. The family Philanthidce contains a half dozen hand- 

 some species, of which the two speciesofCerceris are common. Some 

 members of this genus have been found to provision their cells 

 with beetles. The Trypoxylidee utilize the deserted burrows ot other 

 insects, and store up spiders for their progeny. The only represent- 

 ative of the Mellinidse is very rare and probably supplies flies for 

 its young as an European species is said to prey upon diptera. 

 The Nyssonidae is the second of our families in number of specieS) 



