270 Illinois State Lahoratory of liatural History. 



■deep notch iiDPa which a sulcus extends forwards, theit 

 apices with recurved bristles, and at their base within, 

 the light yellowish stigmata; seventh tooth small, medio 

 dorsal, anal prominence cordate. 



Larva {c). 



From earth in bottom-land, April 17. It is much 

 like the preceding, and probably of the same genus. 



Length about 1\? mm., not essentially different from 

 larva h except on the last segment, which has the 

 truncation surrounded by four acute teeth, an upper 

 and a lower pair, with a broader lateral interval, in which 

 is a very small tooth on each side; the upper teeth bear 

 an apical fascicle of setae, and the yellowish stigmata 

 are at their base within. 



HYMENOPTERA. 



None of the members of thi.s order are strictly aquatic* 

 Some of them, however, concern us in this connection 

 because of their attack upon aquatic forms, either as 

 true parasites or for the purpose of provisioning their 

 nests. The breeding of the parasites of aquatic insects 

 has received very little attention in this country, and 

 much still remains to be done in this direction. 



In the Parasitica, Mr. W. H. Ashmead has kindly 

 worked up our Station collections and prepared descrip- 

 tions of the new species, his article following the present 

 one, and beginning on p. 274. 



Family ICHNEUMONID^. 



Oryphts cyaneiventris Riley MS. 



Common in July on the floating leaves of Potamogeton 

 nutcms^ associated with Hydrocampa olUteralis, under 



•A parasitic hymenopteron, Polynema natans, is able to swim with its wingi, 

 •*.nd seems to be the nearest approach to aa aquatic insert of aay in this order. 



