NYSSONIDiE. 163 



yellow spots on the abdomen, which has the basal ring yel- 

 lowish red in the female. 



The fourth subfamily is the Nyssoiiince, so named from Nys- 

 son, a typical genus. 



The genus Gorytes is truly a mimetic form, closely simulat- 

 ing the genus Odynerus, one of the Vesparice . The front of 

 the head is narrow, while the clypeus is larger than usual. The 

 species are numerous, occurring late in the summer on the 

 flowers of Spiraea. Gorytes flavicornis Harris is polished russet 

 brown, with narrow j'ellow rings on the abdomen, the propo- 

 deum is smooth and polished, and the basal ring of the alidomen 

 is black. A species has been observed in Europe protruding 

 her sting into the frothy secretion of Tettigonitie living on 

 grass, and canying off the insect to provision its nest with. 



Oxybelus is a short, stout, black genus, with whitish abdomi- 

 nal spots, and st0^.it spines on the thorax, while the sessile 

 abdomen is distinctly conical. "Its pre}^ consists of Diptera, 

 which it has a peculiar mode of carrying by the hind legs the 

 Avhile it either opens the aperture of its burrow or else forms a 

 new one with its anterior pair. Its flight is low, and in skips ; 

 it is very active." (Westwood.) 



Oxyhelus emarginatus Say has two oval membranous appen- 

 dages to the metathorax, and is a common black species found 

 abundantly on the flowers of the Virginia Creeper. 



In Xysson the body is a little longer, narrow compared with 

 that of Oxybelus, while the terminal joint of the antennae is 

 thickened, flattened, and excavated beneath. JSfyssoii lateralis 

 Say is dull black, with six light spots on the abdomen. 



The species of Stizus are of large size and easily recognized 

 by their hirsute body, stout legs, triangular silvery clypeus, 

 and the high transverse vertex of the head. The propodeum 

 has a faintly marked triangular enclosure. The species are 

 very rapacious, paralyziug grasshoppers and other large insects 

 with their formidable sting, and carrying them off to provision 

 their nests. Professor S. Tenney has sent us a specimen of 

 the Dog-day Cicada (C. canicularis) which Stizus sjwciosus had 

 thus stung. Mr. Atkinson has observed the same fact, and has 

 found the deep burrows of this species, the hole being three- 

 fourths of an inch in diameter. He has observed it feeding on 

 sap running from a tree. 



