HYMENOPTERA 931 



Except that some have long ovipositors and some short, the various 

 species look much alike. They are parasitic in the nests of solitary 

 bees and wasps. The adults are common on umbelliferous flowers 

 and around logs in which their hosts are nesting. 



A monograph of this family was included by Kieffer ('12) in his 

 paper on Evaniidae. 



SuPERFAMiLY PROCTOTRUPOIDEA 

 The Proctotr lipoids 



The Proctotrupoidea includes mostly very small species super- 

 ficially resembling chalcids or braconids. Most of them are black 

 with the legs and antenna often brownish or reddish. The first three 

 families listed have a fairly complete venation in the front wing. 

 In the other families it is more or less reduced. The hind wing has 

 never more than one closed cell and lacks an anal lobe. The ovi- 

 positor issues from between dorsal and ventral plates at the tip of the 

 abdomen. In most other parasitic hymenoptera it issues from a 

 subterminal cleft on the ventral side of the abdomen. These insects 

 may be distinguished from chalcids by the fact that the pronotum 

 extends back to the tegula. They dift'er from the braconids and ich- 

 neumonids in having never more than fifteen antennal segments. 



A few proctotrupoids are inquilines. The rest are internal 

 parasites of other insects or their eggs. 



The North American Proctotrupoidea were monographed by 

 Ashmead ('93). Note that the first three subfamilies of Ashmead's 

 classification, those in which the hind wings possess an "anal lobe," 

 are now included in the Vespoidea and Sphecoidea. 



The family ROPRONIID/E includes the single genus Ropronia 

 with a few rare species in North America. The adults are about 

 eight millimeters long and have a subcircular compressed abdomen 

 on a petiole. They may be collected among rank herbage in moist 

 woods. The immature stages are unknown. 



The family HELORIDtE includes the genus Helorus with the 

 single species H. paradoxus in North America. It is a black species, 

 about four millimeters long with fifteen -segmented antenna and a 

 petiolate abdomen. The adults may be collected on umbelliferous 

 flowers. The larvae are parasitic in the cocoons of Chrysopa. 



The family VANHORNIID.'E includes the single rare species 

 Vanhoriiia eucnemiddrum occurring in eastern North America from 

 Massachusetts to Virginia. It is a parasite of Isorhipis ritficdrnis, a 

 beetle working in dead wood that is fairly sound. The adult Van- 

 lidrnia has very broad mandibles with the teeth pointing outwards. 

 The abdomen is covered almost entirely by single dorsal and ventral 

 sclerites. See Crawford ('09). 



The family PROCTOTRUPID^,* also called Serphida?, con- 

 tains several closely related genera and about two score North 

 American species ranging from about three to six millimeters in 



*For a monograph of the family see Kieflfer ('14) and for a recent revision of 

 our species see Brues, Jour. New York Ent. Sac. 1919, 27 : 1-19. 



