444 THE CANADIAN NATURALIST. [Bec. 



latter may be seen, by any persons interested in the subject, at 

 the Society's Museum. 



Specimens of the new cable were kindly lent for the occasion by 

 Mr. H. Lyman ; and Dr. Smallwood brought a diagram, taken 

 from a series of soundings, in which the dififerences of level in the 

 sea-bottom between Yalentia and Newfoundland were clearly 

 shown. 



An animated discussion took place after the reading of this 

 paper, in which Principal Dawson and others took part. 



ENTOMOLOGICAL SOCIETY. 



ON A GALL-PRODUCING HYMENOPTER, REARED FROM TRITICUM 



REPENS, LINN. 



By Wm. Couper, Quebec. 



There is a large extent of cleared land in the neighborhood of 

 Quebec which does not appear to be exhaust^ for agricultural pur- 

 poses, and yet it is neglected. The consequence ofthis neglect is 

 that it becomes occupied by innumerable noxious weeds: one of these 

 is the common creeping wheat-grass, Triticum repens of Linnaeus. 

 This grass is attacked by a hymenopterous insect which, I sup- 

 pose, is the yellow-legged or New York barley-fly, Eurytoma 

 fulvipes of Fitch. The insect appears in June, when the female 

 deposits an egg in each joint of the grass, producing a gall as 

 represented in the following figure. 



This grass is most troublesome to the Canadian farmer 

 owing to its creeping habit. " Its long underground stems pene- 

 trate the loose soil in every direction, and, when once they have 

 possession, are very difficult to eradicate, as, broken up by the 

 plough or spade, every fragment vegetates apart, thus renewing 

 and extending the crop. Few plants exhaust the ground so 

 rapidly of nutritive matter, and it can only be got rid of by 

 repeated fallowing or laying down to pasture." If our farmers 

 would appropriate such land to pasture it would help, in a great 

 measure, to remove its present worthless parasite. Although this 

 insect attacks the grass, it by no means lessens its growth; there- 

 fore, if we make no effort to check the increase of worthless plants, 

 depend upon it the insects which are attached to them will increase 



