31 



iKosoma Jiordei. This last outbreak in central New York appears to 

 have been rather widespread and disastrous, for in 1858 Hon. George 

 Geddes, president of the State Agricultural Society, stated that while 

 former!}' a yield of 40 bushels of barley to the acre was expected, they 

 could not at that time reh' upon more than 20, and unless relief came 

 barley growing, on account of the attack of this pest, would have to 

 be abandoned." 



There was a local outbreak of this species in Ontario, Canada, in 

 1807-68, and observed at Wakeman, C'hagrin Falls, and Barr}^ Ohio; 

 Indiantown, Cuckoo, and Paj^nes, Va. ; Albany, N. Y. ; Canada West 

 (William Couper); Ottawa, Canada; and Urbana, Carbondale, and 

 Marshall, 111. So far it has not been reported from the Pacific coast 

 States. Doctor Fitch confined this species to the insect reared by 

 Harris in Massachusetts, and the one working the injuries in central 

 New York as Isosonia fulvipes^ both of which are now known to 

 belong to Isosoma Jtordei. 



LIFE HISTORY 



The species is single brooded. The adults of both sexes, all fully 

 winged, emerge from the straw and grass in late May and early June, 

 o\'ipositing almost immediatel3\ The effect of the larvte on the grow- 

 ing plants begins to show within a short time, and. though the larvae 

 become full grown during June and early Jul}', they remain in this 

 condition within their cells until Ma}^ of the following 3'ear. 



EFFECT OF THE LARV^ ON THP] PLANT. 



The eggs may be deposited in the stem of barley or grass anywhere 

 between the root and the head, even among the lower spikelets of the 

 head. The effect of the larva? may be to cause hard, woody cells, 

 whose outline is indicated only b}' slight discolorations, the outer sur- 

 face of the stem being- smooth and not in the least swollen, the cell 

 being entirely within the walls of the stem, causing no distortion in 

 the straw; or there may be anywhere from one to a dozen galls in a 

 cluster, and these may be either clearly defined or so packed together 

 and cramped as to lose all semblance to the typical galls and take on 

 the appearance of diminutive growths, resembling the black knot of 

 the cherr}" and plum. The straw or grass stem may be enlarged to 

 two or three times its natural size, forming an elongated oval woody 

 growth that pushes its way outward, bursting, as it were, the sheath 

 at base, and showing between the edges. This growth is usually on 

 one side of the stem, just above the joint, and is marked with inter- 

 lacing creases and furrows indicating the outlines of each individual 

 cell, and in many cases sending downward from the lower extremity 

 smali root-like appendages, the use or cause of which it is difficult 



« Trans. N. Y. Agl. Soc, 1859, p. 332, 



