50 



CEREAL AND FORAGE INSECTS. 



OVIPOSITION. 



The process of oviposit ion, as carried on immediately after emer- 

 gence and copulation, is short and rapid. The females crawl care- 

 fully over a seed head for a few seconds until they find a seed, the 

 glumes of which present the best adaptabilities for egg laying. This 

 stage is reached just as the flowers have been shed and the glumes are 

 open at the apex to their greatest degree. When the female has 

 selected the seed she takes up a position upon the apex, her abdomen 

 elevated slightly above the tip, and immediately extends her oviposi- 



Fig. 27.— Sorghum heads, showing four successive stages in the opening of the sheath or "boot." 



f Original.) 



tor, pushing it within the seed until it is fully extended; then, with a 

 rapid pistonlike motion, she places the egg. It is doubtful if more 

 than one egg is deposited by a single female in the same seed. Dis- 

 sections of seed observed to have been oviposited in by but one female, 

 and but once, have not, during the writer's investigations, revealed 

 more than one egg. 



However, it is no uncommon sight to observe several females follow 

 one another in quick succession, ovipositing within the same seed. 

 Numerous examinations of infested seed have revealed as many as 



