102 



generations befure unknown among these insects in tliis country, was 

 represented in my rearings from wlieat stubble, collected from about 

 NeAV Harmony and Princeton, by tlie spring form miiiKfiiiu. 



Isosoma tritici Fitch was also reared from wheat straw from these 

 localities. Specimens of the latter occurring among the former are quite 

 strongly contrasted, the latter being quite large for tliese insects and pos- 

 sessing fully developed wings, whereas tlie former are much smaller and 

 wingless. Reared also from EUjnnis ciryiiiiviis, an entirely new food plant 

 for the species. 



LsosoiiKi iiKicHliifinii Howard was reared in considerable numbers from 

 the stems of clieat, liromiis srriiHiins. 'J"hi' si)('cies was described from 

 Individuals collected l)y me about Lafayette during .lune, ISSo, and May, 

 188G, but the food plant has up to tliis time remained unknown. 



Isosomd albomacvlatii/i Ashmead, origina.lly described from AVest Vir- 

 ginia, was reared from lirnniiia scciiliiiiis in great nniiiliers, ;ilso to a lesser 

 extent from tlie stems of Kli/iinis riri/'micKs. 



Isosoiint cli/ini Frencli was rc-ired in in'ofnsion from Kli/iim.s. This 

 species, at one time supposed to lie a wlieat ins(>ct, confines itself strictly 

 to the grasses. I liave iie\ci- rcai-cd it from whe.it straws and liave never 

 reared Ixohoiiki iiniiKU ri-om anything else except wheat. 



Isitsoiiiii I fliiripi's) liordii Harris was reai'cd fi'oni steins of Kli/nnis cdii- 

 (i(h')isls and in such niunl)ers as to give economic importance to the fact. 

 The rearing of the .Joint Woi'in species. /. lionlri. and one of the wheat 

 straw worm species, /. frilici. fi-oiii Elininix. lioth of wliicli are wlieat in- 

 sects, shows very jilainly that though the farmer may overcome these in 

 his cultivated fields, unless he is careful to destroy tliese grasses growing 

 along roadsides and in unciiltivalcd ti(>lds. ;i continual rcinfestjition will 

 be going on, and he must tight his foes in the grasses as well as in his 

 cultivated grains. Besides these, thei'e is a species of Isosoma, of which 

 I have only been aide to rear the male, Init the larvic of which infest the 

 stems of Triciispis scslo-oiticx. and I have r(>ared tliese from stems col- 

 lected near Orleans, Indiana. There is probably still another species of 

 Isosoma. at present not distinguishable from /. lihiifntiis Howard. Tliis 

 last had until now been known '>nly fi'om rye straw in California. I did 

 not rear this from Indiana, but in Illinois the common cheat, Bromus 

 secdJiiiiis, appears to he its sole food plant. The larva:" are found in the 

 stems, and as the stems of cheat in Indiana contain an abundance of 



