42 



Mr. Howard asked whether Prof. Forbes considered his experiments with the 

 apple plant louse were satisfactory. 



Prof. Forbes thought not entirely but they were the best they could do under 

 the circumstances. 



Mr. Fletcher asked whether the habits of different broods in species which 

 migrated from one plant to another were not very different and therefore difficult 

 to experiment with — as, for instance would the hop inhabiting form of Pkorodon 

 humidi live upon plum if placed there artificially and vice versa. 



Prof. Riley thought it would not. It is very difficult to do artificially what 

 nature does in her own time and in her own way. Sometimes an insect will not 

 colonize upon a plant at a certain season, to which at another time of the year it 

 migrates naturally. He asked if the experiments made upon ihe root forms were 

 done carefully as there are many species which resemble each other which have 

 root forms. 



Prof. Forbes stated that great care had been taken in carrying out the 

 experiments. 



Prof. Forbes read a paper " On the life-history of White-grubs, with descrip- 

 tions of new stages." Current mistakes with regard to the life -histories of these 

 injurious insects were pointed out. Several species of Lachnosterna were observed 

 to reach the imago state in the autumn instead of in spring as usua lly stated and 

 the differences between groups of larvae were pointed out. 



The paper was discussed by Messrs. Smith, Howard, Forbes and Riley, who 

 confirmed many of the points made in the paper. 



Mr. C. A. Hart read a carefully prepared paper on " The life-history of Wire- 

 worms," in which he drew particular attention to distinguishing characters by 

 which these larvae might be divided into groups. 



The paper was discussed by Messrs. Cook, Gillette and Bruner. 



Prof. Cook had found that one crop of buckwheat will not prevent injury the 

 next year. 



Mr. Fletcher gave some " Notes upon Injurious Insects of the year in 

 Canada," Cut- worms of various kinds had been locally abundant. Agrotis turris 

 had been destructive in gardens to fiowers and vegetables. Hadena arctica and 

 H. devastatrix had injured fall wheat and grasses in the spring. He was more 

 than ever in favour of the poisoned trap remedy for cut-worms. Agrotis fennica 

 had injured clover. The caterpillar of Pieris rapce had been very troublesome, 

 but was easily destroyed with pyrethrum powder diluted with four times its 

 quantity of common flour or slaked lime. 



Plutella cruciferarum had also done much harm to cabbages in the 

 North-west Territories and British Columbia. This is much more difficult 

 to destroy with pyrethrum than the last named. The Cabbage Root-maggot 

 had attacked cabbages severely, but had been successfully destroyed by 

 syringing about half a cupful of hellebore tea round each root and then 

 hoeing the soil well up round the stem. He had made some interesting studies 

 of the Hessian fly which agreed in the main with those published by Prof. 

 Forbes in a late bulletin. Spring wheat sown in the end of April had been 

 attacked at the root in the same way as wheat is injured by the autumn brood. 

 From the same wheat plants he had bred the Hessian fly, the Wheat Bulb-worra 

 and Oscinis variabilis. Insects injurious to fruit trees had been represented by 

 the Plum Curculio, the Codling Moth, the leaf roller of the apple and the Canker 

 worm. All of these had been successfully treated with Paris green. Observa- 



