1899] ENTOMOLOGICAL SOCIETY. 107 



Cereals. 



Grain crops throughout the province have not been injured to any large extent by- 

 insects. The Wheat Jointworm, which last year did some damage, has not re-occurred, 

 and the same satisfactory report may be made with regard to the outbreak of the Wheat 

 Midge, which appeared last year along the shore of Lake Ontario in the Niagara penin- 

 sula. The Hessian Fly, that old time enemy of the wheat grower, was rather more abun- 

 dant than usual in Western Ontario, and letters were received asking as to the best way 

 of preventing loss. Wireworms were troublesome in several places, and some practical 

 treatment to prevent loss by these insects is much needed. 



The Pea Weevil nas done much harm this year. Farmers and pea growers are care- 

 less about getting their seed fumigated, and there are many complaints that this serious 

 pest is increasing. In our last report, at page 78, full instructions were given as to the 

 easiest and best means of treating seed pease to destroy the weevils. They were briefly 1 

 (1) fumigating the seed with bisulphide of carbon, or (2) the holding over of seed for a year. 



The Destructive Pea Aphis (JVectarophora destructor, Jnsn.). — By far the most serious 

 attack upon field and garden peas during the past summer was by a previously undescribed 

 species of plant-louse. It is very remarkable that a species should suddenly appear; as 

 this one did, in sufficient numbers to destroy millions of dollars worth of produce in a few 

 days, and that it should have been previously so rare as to have entirely escaped detection 

 and description by Entomologists. Such, however, was the case. The Destructive Pea 

 Aphis occurred in vast numbers in several parts of Canada and the United States. 

 Specimens of the insect and reports of its ravages were received from widely separated 

 places, in a line extending from the Maritime Provinces to the Lake Erie counties of 

 western Ontario, and from the Great Lakes down to the Southern States. The species 

 has been worked up and described by Prof. W. G. Johnson, of College Park, Md., and an 

 interesting account of it by him was read at the eleventh annual meeting of the Associa- 

 tion of Economic Entomologists last August which will appear in the report of that meeting, 

 Prof. Johnson said "the growing of peas in Maryland is a very important industry, and 

 reliable conservative authorities place the loss this season at $3,000,000. the principal 

 cause being the Pea Louse. In many cases the destruction was complete, varying from 

 mere garden patches to hundreds of acres." The States in which most injury has been 

 recorded are Maryland, Virginia, North Carolina, Pennsylvania, New York, New Jersey 

 and Delaware. 



The two most notable occurrences of the Pea Aphis in Ontario were at Freeman, 

 reported by Mr. G. E. Fisher with specimens, and at Ottawa where the insects were 

 found in large number3 from August until the end of October. The attacks upon field 

 peas at Ottawa were unimportant, but the sweet peas in some gardens were seriously 

 injured. For field peas it is difficult to apply a remedy, owing to the way in which this 

 crop covers the ground, but with Sweet peas, spraying with tobacco and soap wash (10 

 lbs. of native tobacco leaves and 2 lbs whale oil soap in 40 gallons of water) was found 

 very effective. Many predaceous and parasitic insects were observed at work. On the 

 Experimental Farm larvae of Syrphus flies and Lace- winged flies were common and beetles 

 and larvae of the two Lady-bird beetles, Coccinella 9-notata Hbst and Hippodamia convergent 

 Guer, were extremely abundant, as well as the hymenopterous parasite Praon cerasaphis> 

 Fitch. In the garden of Mr. Colling wood Schrieber, in addition to the above, large num- 

 bers of a new species of Aphidius* were detected. Unfortunately both the Syrphus flies 

 S. ribesii, Fab., and the nine spotted Ladybirds were attacked themselves by para 

 sites ; but nevertheless they reduced very materially the occurrence of the Pea Aphis. As 

 well as the above-named, larvae of a minute dipterous parasite (Diplosis ?) and a fungous 

 parasite appeared in small numbers in all colonies of the aphis and doubtless played 

 an important part in bringing down the numbers. The undue increase of the various 

 kinds of plant lice seems to be particularly affeoted by meteorological conditions, and, as 

 in the past there is no record of serious injury to the pea crop by these insects, there is 

 every reason to hope that we shall net have anothor visitation similar to that of 1899 for 

 some years. 



* Since named Aphidius Flctcheri by Mr. Ashmeaa. 



