6 



umerates a number of insects which prey upon this pest in the various stages of its 

 growth, and among them refers to a species of Lehia, one of the active members of that 

 family of beetles known as Carabidse, all of whom devour other insects. This species, 

 Lp-bia grandis, is there said to be rare in Ontario. The first examples of this insect which 

 I remember capturing were taken last year at sugar when trapping moths, and I believe 

 it is the only species belonging to that family which I have ever taken in this manner ; 

 several of them were found feeding on the sweet liquid on dark nights about 10 o'clock. 

 Early this fall I received a letter from Mr. W. E. Cold well, of Constance, Ont., announcing 

 the appearance in large numbers of a friendly insect, which was devouring the larvae of 

 the Potato Beetle, and proving a very effectual check on their increase. This letter was 

 accompanied by specimens of the insect, which, to my gratification, I found on examina- 

 tion were examples of Lehia grandis. A few weeks later a farmer in this neighborhood 

 called on me with the information that he had observed large numbers of an insect which 

 he had not seen before, devouring the larvae of the Potato Beetle. He brought no speci- 

 mens with him, but from his description of the insect I have every reason to believe that 

 it was the same Lehia. Since then I have occasionally met with examples of this friendly 

 visitor hidden amongst the leaves of plants, a common place of resort for it during periods 

 of inactivity. 



The Hessian Fly, Cecidomyia desiruclor, which appeared in force in many counties of 

 our Province last year, and which it was feared might again become a serious trouble, has 

 happily almost disappeared. I have not heard of any serious loss from this pest during 

 the past season. Should any of you desire, at any time, information in reference to the 

 life history and habits of this insect, I would refer you to a very practical paper in our 

 last annual report, by the Hev. C. J. S. Bethune ; also to a more elaborate paper by the 

 same distinguished Entomologist in our report for 1871. 



The Cabbage Butterfly, Pieris rapce, still continues its ravages, but does not seem to 

 be quite so abundant this year as it was last. Water heated to near the boiling point has 

 been used with success in destroying the larva, without injuring the cabbage. Strong de- 

 coctions of Cayenne pepper and Smartweed {Polygonum ?) have also been spoken 



higlily of ; but I look forward with far more confidence to a remedy provided by nature 

 which is gradually making itself felt. I allude to that tiny little friendly parasitic fly, 

 Pteromalus piiparum which is rapidly increasing in our midst. A few days since, while 

 watching some of the full-grown larvae of the Cabbage Butterfly which were feeding on 

 Nasturtium leaves, I was much gratified in witnessing the method of attack which this 

 parasite adopts. Settling herself quietly down on the back of the caterpillar, near the 

 terminal segments, with her head tov/ards the caterpillar's head, she paused awhile ; then 

 with a sudden movement of her ovipositor, so quickly that the motion almost escaped de- 

 tection, she thrust an egg under the skin of her victim. The caterpillar seemed startled, 

 and quivering, jerked its head and anterior segments suddenly about, and then quieted 

 again ; the little tormentor meanwhile sitting perfectly composed on the spot where she 

 first settled. Presently another thrust was made, followed by further uneasy movements 

 of the larva, and in this manner, in the course of a very few minutes, quite a number of 

 eggs were deposited. The caterpillar did not seem to be conscious of the cause of its 

 troubles, nor, indeed, of the presence of its enemy, excepting when the thrusts with the 

 ovipositor were made. On drawing a little nearer for the purpose of better observing this 

 interesting operation, the tiny creature took alarm and flew off. Further examination 

 revealed the presence of several more of these little friends, busily searching for further 

 specimens to operate on. The eggs deposited soon hatch into little grubs, which even- 

 tually devour the body of their victim, and after it has entered the chrysalis state, eat 

 small holes through the chrysalis, and thus make their escape. It has long been an un- 

 settled point among Entomologists as to whether this parasite operates on her victim in 

 / the larval or chrysalis state, the weight of opinion being hitherto in favour of the view 

 that the chrysalis is pierced and the eggs deposited in it ; but from the observations here 

 detailed it would appear that the eggs are usually, if not invariably, placed in the nearly 

 full-grown larva. 



At the same time I observed an insect belonging to the true bug family, Hemiptera, 

 with its proboscis thrust into one of the same caterpillars, quietly sucking out its contents, 

 the half-emptied victim vainly endeavouring to escape. As this bug was immature, I was 



