SPHEGIDJE. 



167 



sons, was frequently observed by Mr. C. Cooke to attack the 

 cockroach. The cockroach, as if cowed at its presence, im- 

 mediately yields without a struggle. The Ampulex stings 

 and paralyses its victim, and then flies away with it. 



Chlorion is closely allied, containing blue and metallic green 

 species, often with golden yellow wings. Chlorion cyaneum 

 Dahlb., a blue species, is found in the Southern States. 



The genus Priononyx "differs from the genus Sphex in hav- 

 ing the claws quadridentate beneath at their base ; the neura- 

 tion of the wings and the form of the abdomen are the same as 

 in Harpactopus" which is found only in the tropics and Aus- 

 tralia. Priononyx Thomce is found from South Carolina to 

 Brazil, including the West Indies. 



The genus Sphex is quite an extensive one. The head is as 

 wide as the thorax ; the antennae are filiform, mandibles large 

 and acute, bidentate within, the teeth notched at their base, 

 forming a rudimentary tooth, the apical tooth being acute. 

 The thorax is elongate-ovate, truncated behind, with a trans- 

 verse collar (prothorax). The fore wings have one marginal 

 and three submarginal cells ; the marginal cell elongate, rounded 

 at its apex ; the 

 first submarginal 

 cell as long as the 

 two following. The 

 abdomen is pedun- 

 culated, conically 

 ovate, and the an- 

 terior tarsi are cili- 

 ated in the females. 



Sphex ichneumo- 

 nea. Linn. (Figure 

 90) is a large rust- 

 red species, with a 

 dense golden pu- Fig. 90. 



bescence. It is common from Massachusetts southwards. In 

 the last week of July, and during August and early in Sep- 

 tember, we noticed nearly a dozen of these wasps busily en- 

 gaged in digging their holes in a gravelly walk. In previous 

 seasons they were more numerous, burrowing into grassy 



