24 



PREVIOUS RECORD OF THE INSECT. 



About the year 1848, in central Virginia, throughout the country 

 adjacent to Charlottesville, Albemarle Count}^ and Gordonsville, 

 Orange County, the wheat began to suffer seriously from attack of 

 what was at that time called the joint-worm. In 1851 the wheat in 

 Albemarle Count}^ was, much of it, not worth the harvesting. In 

 1851: the ravages of the pest had become so serious that a '' joint- worm 

 convention " was held in Warrenton to devise means for controlling it 

 and preventing, if possible, its further ravages, as by this time it had 

 become almost impossible to raise wheat at all in the infested terri- 

 tory. The action of this convention was to recommend a better sys- 

 tem of cultivation, the use of guano and other fertilizers to promote 

 the rapid growth and early ripening of the grain, and the 1)urning of 

 the stubble after harvest. 



Fig. 8. — Isosmna tritiei Fitch: adult of the joint- worm, much enlarged (from Howard). 



Looking back to this period, our later-day entomologists can hardly 

 understand how there should have been an}" difficult}' in determining 

 beyond a possible doubt the author of all of this destruction. Doctor 

 Fitch, who, it seems, received some of the growing wheat plants 

 infested with the larvte from that locality, always insisted that he found 

 a cecidom3dan larvae inhabiting cells like those occupied by the joint- 

 worm and that these were the true depredator, and, though he continued 

 to stoutly defend his determination, we have yet to discover a Cecido- 

 mj'ia either causing or inhabiting such a cell or gall in the wheat plant. 

 From all that has been since learned i-elative to these insects it is clear 

 that the ravages were those of this species, with, perhaps, individuals 

 of the preceding species intermixed among them. As a matter of 

 history it may be stated that Doctor Fitch was still unconvinced that 

 the joint-worm, and not a dipterous insect, was responsible for the dam- 



