198 WASP STUDIES AFIELD 



Howard gives a good figure of this wasp in The Insect Book, 



PI. 5, fig. 18. 



Davis 15 found the following prey in the nests which he 

 opened: Atlanticus dorsalis, three in each of two nests and 

 five in another, and elsewhere he saw a wasp carrying a 

 Conocephalus triops. Packard, in his Guide, says they use 

 Orchilimum vulgare or O. gracile. Our records mention 

 only Orchelimum in their nests. All of these are the long- 

 horned grasshoppers, for which they show a preference. 



A Locust-hunter that Makes Twin Cells. 



All summer long we had scoured this bare spot in the 

 field almost daily (fig. 2), yet it was the middle of September 

 before we discovered the first burrows of an unknown wasp. 

 The mouth of the hole, open, is about three-sixteenths 

 inch in diameter, clear-cut, and might easily be mistaken 

 for a beetle's or spider's hole, while the neat little mound 

 of dirt nearby is almost indistinguishable from the dainty 

 little ant-hills which abound in the field. Sphex pictipennis 

 carries out and piles up the dirt in the form of little chips; 

 Priononyx and Bembix kick it out as dust, but this species 

 brings it out and piles it up in granular form, only a trifle 

 coarser than that of the tiny ants. She must understand 

 the art of keeping herself modestly inconspicuous, and must 

 work without all the bombastic commotion in which Bembix 

 indulges, for we have never been able to catch her at her 

 work. 



One of these piles of granules a/oused our curiosity on 

 September 15. We examined all the earth about it care- 

 fully, but could detect no trace nor scar on the ground where 

 the soil had been disturbed, so with the trowel we shaved off 



15 Journ. N. Y. Ent. Soc. 19: 218. 1911. 



