122 , THE CANADIAN ENTOMOLOGIST 



in July, 1911, the place is visited to see if moeseri can be found 

 there. Numerous larvae are located, and in 1912 the colony is 

 found to be still flourishing. There is considerable difference 

 apparently in the time at which the hibernated ova hatch, due 

 to the very moist conditions they endure. While the egg may 

 withstand inundation very well, the young larvae cannot, and, 

 as with marginidens working in Cicuta and Sium, both water- 

 loving plants, many tardy larvae occur. Though neither the ova 

 nor the first stages were observed, the first week of June can be 

 figured as their date of general emergence. The stems are entered 

 several inches above ground, and a more or less extended tunnel 

 drilled upward. As they become larger, the boring of necessity 

 becomes small for them, and they turn downward in the under- 

 ground portion of the stem or root. The stems are often weakened 

 so as to fall, and there are several openings made whereby the 

 frass is thrown out. These castings form in little whitish mounds 

 and become a conspicuous clue to the hidden host. Thus far, 

 parasitism seems abnormally low, but one Hemiteles attack having 

 been noticed. 



As moeseri is so clearly a denizen of the wild woodland or 

 swamp, it seems a coincidence to have been first met within the 

 confines or immediate vicinity of such large cities as Montreal, 

 Buffalo or New York. In southern West Chester Co., N.Y., 

 and on the opposite shore of Long Island no infestations have 

 been found, though it is true no stations of the plant were met 

 that could be expected to support flourishing colonies. The fol- 

 lowing larval stages were observed: 



Stage IV. — Head normal for group, polished, pale brown, 

 marked with a black line at the ocelli, which extends posteriorly 

 oblique across the epicranium, labrum and mouth parts black, 

 seta at tubercle VIII seems longest. Body cylindrical, thoracic 

 joints have the skin puckered, colour is a livid cast of umber brown, 

 which shows on joints four to seven inclusive as a dark band or 

 girdle, the remaining joints relieved by the white longitudinal 

 lines; the dorsal line is unbroken, but its continuation across four 

 to seven is by the merest thread; subdorsal line wider, but breaks 

 abruptly at joints four to seven; subspiracular shows on thoracic 

 joints, on eight to twelve is fused with the white of the ventral 



