19 



by June 10, nearly all have transformed to the adult .sunnner form 

 i^grande)^ which begins to appear about June 1, reaching- its maximum 

 in point of numbers about June 20, though I have found an occasional 

 individual as late as the 27th of that month. In ovipositing, uiinutuni 

 seems to prefer the lateral stems in which to place her eggs, thus 

 leaving the central stem unaffected. With the summer form {(jrande) 

 this selection is reversed and the largest and most thrifty stems are 

 selected. Spots of rank growing, thinl}^ placed grain will suffer worse 

 than the more denseh' growing areas. 



OVIPOSITION OF THE SLTklMER FORM (gRANDE), 



Nurtured in the midst of the embryo head, we would naturall}" look 

 for an adult insect differing somewhat from the one developing from 

 larvae whose food is of a coarser and tougher nature, and in this case, 

 whether as a coincidence or otherwise, we have a much larger insect 

 with fully developed wings, forming in consequence the migrator}^ 

 brood of the species. That these females wander about from lield to 

 field is shown by the fact that thej^ may be captured during June by 

 sweeping over the grass lands with an ordinary insect net, such as is 

 used b}' entomologists for this purpose. 



The method of oviposition between the spring and summer forms 

 does not differ materially, except as the difference in the conditions of 

 the plant makes slight \^ariations necessary. The former nuist place 

 her eggs in the very 3^oung plant comparatively close to the surface 

 of the ground, while the latter seems to tr}" to get her Qgg immedi- 

 ately above the uppermost joint of the wheat stem within her reach. 

 At the season of the 3"ear when this takes place the upper, and fre- 

 quently the joint next below, is not uncovered by the leaves and 

 sheath, but the majority of the eggs are placed, singlv, just above 

 either the second or third joint below the head, and rarely above the 

 upper joint. The significance of this to the farmer is that very few of 

 the larva? hatching from these eggs will be taken awa}" with the straw, 

 but, on the contrar}", left in the field in the stubble. If the reverse 

 were the case, and most of the larva? removed with the straw to the 

 barnyard, there to be either run through the stables or similarly util- 

 ized, in most cases hardly an individual would get back into the wheat 

 fields in spring, for it nuist be remembered that at this period the 

 adults are wingless and incapable of flying. The method of oviposi- 

 tion is shown in tig, 6, a, and the point where the Qgg is deposited in 

 the straw is shown in figure 6, h^ the transverse line showing the track 

 of the ovipositor. To place her &gg^ the female takes up her position 

 • just above the joint, with her head downward. She then straightens 

 her legs, thus throwing her body away from the stem, at the same 

 time bringing her feet almost directly l)eneath the body. She now 

 brings the abdomen downward and forward between her legs, much 



