THE CANADIAN ENTOMOLOGIST 147 



the search had narrowed down to the ferns, with usual acumen, 

 he soon located the great colony of the Meadows. It developed 

 the common Osmundas are the ones chosen, both 0. regalis and 0. 

 cimiamomea being infested. Whether 0. daytoniana is also bored 

 did not develope, since that species did not occur here, being a 

 denizen of dryer places. While it is a surprise this common fern 

 proves the food-plant so long sought, Osmiinda regalis being the 

 favourite, and that negative results had followed its examination 

 in hundreds of cases previously, the prominent feature is the 

 localized colony encountered, with the evidence of its probable 

 antiquity. From twenty years' observation on the growth of 

 Osmiinda under our windows, we do not hesitate to state that most 

 of these individual plants represent fifty years development at 

 least. The gnarled, ruminating root-stocks are elevated 59 to 60 

 cm. above the level of the quaking morass, in the efifort to get 

 above the water and from the nature of the yearly accumulations, 

 and show the borings of preceding generations. 



The presence of the larva in 0. regalis is not easily noted. 

 There is no wilting or drying of a conspicuous frond as happens 

 with the other fern borers. The newly emerged larva enters a 

 miniature stipe whose uncoiled, tender tip has sprung up but three 

 or four centimeters, and in a few days has tunnelled down into the 

 root-stock. This dies, it is true, and is some evidence, but a 

 peculiarity with this fern in this locality seems to be that many 

 more fronds start than eventually mature, what appears to be a 

 fungous blight nipping some in their tender incipiency. Further, 

 a dipterous larva bores these young stipes and causes them to die, 

 so that we find two other similar results produced at the same time 

 in the plant, as is occasioned by the working of speciosissima. As 

 the larval period lengthens, the frass thrown out is the only indica- 

 tion, and this is not in the usual well-formed pellets, but a rusty- 

 brown, mud-like deposit. Even this sign is hard to detect for the 

 fruiting fronds send down their brown inflorescence, which, with 

 the chaff-like scales from the stipes sprinkle the root-stock and 

 help to smother the meagre clues. So the apprehension of this 

 larva is not as easy as with most others, and the surprise greater, 

 when, at maturity, one of these old roots is cleft open, disclosing 



