NO. 2334. NORTH AMERICAN ICHNEUMON-FLIES— CUSHMAN. 273 



include Demo'phvrus Thomson, said to have the femora incrassate 

 but not toothed. 



Mostly rather stout species, the compression of the abdomen not 

 embracing second tergite; head strongly transverse, temples sloping; 

 eyes and ocelli large; antennae somewhat more than half as long as 

 body; thorax stout; notauli distinct anteriorly, obsolete posteriorly; 

 sternauli obsolete; propodeum rounded; completely areolated; areolet 

 very rarely defined, if so oblique and petiolate; hind femur more or 

 less swollen and with a more or less distinct tooth beneath situated 

 from shortly behind middle to apical third, frequently followed by a 

 row of denticles; hind trochanters short; abdomen less than twice 

 as long as head and thorax together; first tergite longer than second, 

 not enclosing sternite; ovipositor more than half as long as abdomen. 



The followmg key includes both the subgeneric and specific char- 

 acters of the North American species. Ashmead's genus Pristomen- 

 dea, based on the size and position of the femoral tooth, the shape of 

 the areola, and the form of the nervellus must be considered as a 

 synonym of Pristomerus, since all of these characters are subject to 

 great variation. Neopristomerus Viereck is so much more closely 

 allied to Pristomerus than to any of the other genera of the tribe as 

 here treated that it must be considered subgeneric. Moreover, the 

 two cliaracters given by Viereck are not always associated. The eyes 

 throughout Pristomerus vary greatl}- in their relation to each other, 

 especially in the male. The obsolete cubitus and subdiscoideus do 

 not furnish an absolute character, for some species have these veins 

 thick for a short distance and then rather suddenly weakening, though 

 still distinct to the apex of the wing. The species dubia Brues, colora- 

 densis Brues, and jmcificus Cresson are not represented in the mate- 

 rial studied, and their insertion in the key is based on the characters 

 ascribed to them b}^ Brues ^ in his key to species. 



KEY TO NORTH AMERICAN SPECIES. 



1. Wings with an areolet; second discoidal cell very narrow at base; ovipositor 



not sinuate near apex (subgenus Areola pristomerus Cushman) 2. 



Wings without an areolet; third discoidal cell not especially narrow at base; 

 ovipositor sinuate near apex 3. 



2. First joint of flagellum longer than second; propodeum not excavated be- 



hind; second tergite shorter than first, striate throughout 



smithi, new species. 

 First two joints of flagellum equal in length; propodeum excavated behind; 



second tergite as long as first, shining on basal third dubia (Brues). 



3. Cubitus and subdiscoideus extending to margin of wing, former straight or 



slightly curved at base, but the base not directed sharply forward; second 

 abscissa of cubitus longer than intercubitus (subgenus Pristomerus Curtis) . [4. 

 Cubitus and subdiscoideus not extending much beyond recurrent, being 

 represented beyond by folds or streaks; second abscissa of cubitus shorter 

 than intercubitus (subgenus Neopristomerus Viereck) 8. 



1 Psyche, vol. 18, lUil, p. 23. 

 181404—21— rroc.N.M.vol..'i8 18 



