1900] 



ENTOMOLOGICAL SOCIETY. 



67 



these are shaken were covered up and a large proportion of them destroyed." The cul- 

 tiv^ation was not repeated until the third day, as it usually required 48 hours to destroy 

 the insects when covered with earth. Another method which was tried with considerible 

 success, consisted of a brush which dislodged the insects so that they fell into a pan con- 

 taining coal oil and water, and dragged between the rows. In this way a bushel of plant 

 lice were caught to each row of peas 1 25 rods long. Spraying was tested, but it was 

 abandoned because no spray could be found which would destroy a large enough percent- 

 age of the insects to warrant the expense of the operation. An extensive experiment, 

 however, covering 600 acres where the plants were brushed and cultivated every third 

 day for a period of two weeks, forty men being employed, was very successful. In this 

 manner the entire field was saved, netting the owner from 25,000 to 30,000 cases of peas 

 ot two dozen tins oach. It is also stated that a field not far distant where nothing was 

 done, was to ally ruined. As is usually the case with all kinds of plant lice when they occur 

 in excessive numbers, the Destructive Pea Aphis has been vigorously attacked by many 

 kinds of parasites, which at Ottawa, at any rate, have had a remarkable effect in reducing 

 its numbers Although the plant lice were extremely abundant in some places, they were 

 almost totally wiped out on one or two occasions by certain of these enemies. The most 

 useful parasite at Ottawa was a small dipterous fly, probably of the genus Diplosis. 

 The small orange maggots of aboat a sixteenth of an inch in length crawled about 

 among the colonies of plant lice and destroyed them in large numbers, piercing their 

 bodies with their mouth parts and sucking out their juices in the same manner as is done 

 by the larvae of Syrphus flies. When fall-grown these larvse spin a small close cocoon 

 either in the angles of the leaves or stem, or falling to the ground make a cocoon of silk 

 with particles of sand attached. There were continuous broods of this useful parasite 

 throughout the season, and the minute gray midges could be seen about the infested plants 

 at all times. The last brood spun their cocoons in the middle of October, and the larvae 

 will remain in them until next spring. Several species of lady bird beetles, Syrphus flies 

 and lace-winged flies were also abundant, as well as species belonging to the hymenop- 

 terous genera Praon and Aphidius. The first of these emerges from its host and spins a 

 cocoon beneath the dead body. The latter passes through all its stages inside the body 

 of the plant-louse and when mature eats its way out through a circular hole. 



Fodder Orops. 



The CloVer E,oot-borer {Bylastinus obseurus, Marsh = , Hy- 

 lesinus trifolii, Muell., Fig. 24) — The Clover Eootborer gener- 

 ally occurs in a few localities in Canada every year, but is seldom 

 the cause of much harm and this will be more and more the 

 case not only with this species, but with the Large Clover 

 1 Weevil (^Phytonnmus punciatus), as farmers get more into the 

 way of sowing clover to a larger extent as a green fertilizer 

 and plough it down after the first crop. During the past 

 summer the Clover Root-borer was observed doing some harm 

 in old fields of clover but also in some new ones right across 

 the province. The worst occurrences were near London, at 

 Picton and in a small patch at Ottawa. Clover which is 

 infested flowers irregularly and the plants have an unhealthy 

 appearance. The insect may be found in autumn in all stages 

 in the roots of clover plants ; the beetle comes to full growth 

 late in autumn and remains in its burrows until the following 

 spring. The remedy for this insect is a short rotation. The 

 value of clover as a fertilizer is now so well known that far- 

 ^*' mers do not hesitate to plough down their meadows as soon as 

 V they find traces of this insect. This should be done as soon 

 --f^ as there is a pretty good growth on the ground after the first 

 crop of hay has been removed. 



The Large Clover Weevil {Phytonomus punctatns, Fab.) 

 found to be abundant in the larval condition in a field, near Picton, Out., which 



