5 



Gallerki cereana; the Carpet Moth, Tinea tapetzella ; the Clothes Moth, Tinea vestianella ; 

 the Bacon Beetle, Dermestes lardarius, and several others of lesser note. 



It cannot be denied that there has been some reciprocity in the matter. We have 

 given Europe the noted Phylloxera vastatrix, which has inflicted damage to the extent of 

 millions of dollars on the vineyards there ; they have also received now from us the 

 much-dreaded Colorado Potato Beetle. 



During-the past season we have had a fair share of destructive insects. The Forest 

 Tent Caterpillar, Clisiocampa sijlvatica, has again been numerous in the district about 

 London and in many parts west of it, but not so abundant as last year. The severe frosts 

 in May destroyed myriads of the very young larvae then newly hatched, and later in the 

 season there prevailed among the nearly full-grown larvae in some localities a strange 

 disease which carried them off by hundreds. I myself saw large numbers of them still 

 retaining their hold on fences and tree trunks, which, when touched, were found quite 

 dead, and so decayed as to burst with a very gentle handling. Very many have also been 

 destroyed in the larval state by parasites ; probably one-half or more will perish from this 

 cause alone. Birds also have devoured many of them. On one occasion the crop of a 

 black-billed cuckoo, Coccygus erythropthaliims, was brought to me packed entirely full of 

 these larvae. Even their clusters of eggs, which they deposit in rings upon the twigs of 

 trees, are not free from attack. Last winter I discovered a species of mite preying upon 

 the eggs and devouring them rapidly ; many clusters were found entirely destroyed in this 

 way, others partially so, and as each cluster would contain probably two or three hundred 

 eggs, some idea may be formed of the benefits conferred upon us by these tiny mites. 



The Colorado Potato Beetle is still spreading eastward through the Maritime Pro- 

 vinces, and has this year reached St. Johns, New Brunswick, but it is no longer the fear- 

 ful evil at first anticipated, and our farmers battle with it confidently, knowing that with 

 a little perse\'erance in the use of Paris green, they can ride victorious over this formidable 

 foe. The use of this poisonous substance has provoked much discussion, and unnecessary 

 alarm has been excited by some writers, who have expressed grave fears that the use of 

 so much Paris green would eventually poison the soil to such an extent as to render it per- 

 manently unfit for the growth of other crops. Several years ago Prof W. K. Kedzie, of 

 the Michigan Agricultural College, when experimenting in this direction, demonstrated 

 that water charged with carbonic acid or ammonia dissolved a certain portion of the Paris 

 green, but that this was quickly converted into an insoluble and harmless compound by 

 combination with the iron which exists in almost every soil. As rain water always con- 

 tains more or less of these ingredients, it is more than probable that the small portion of 

 this poison used on potato fields soon loses its poisonous properties in this manner. In 

 any case, one pound of the green spread uniformly over an acre of soil would only amount 

 to less than one-sixth of a grain to the square foot, so that were the poison to remain un- 

 changed, this minute portion might be added to the soil annually for a century without 

 producing any perceptible deleterious effects on plant growth. It is to be regretted that 

 any one should attempt to excite needless alarm in this way. Caution should be urged 

 in handling this powerful poison, and it is often the case that more is used than is needed ; 

 these points are important and cannot be too often referred to. Paris green is best and 

 most economically used with water in the proportion of one teaspoonful of the powder to 

 a pailful of water, kept well agitated and sprinkled on the potato plants by means of a 

 hand whisk dipped from time to time into the liquid. If the Paris green is pure this pro- 

 portion is ample, but too often this useful compound is largely adulterated, a practice 

 which some dealers are tempted to adopt from the eagerness with which a large portion 

 of the public run after cheap goods. Paris green is frequently adulterated to the extent 

 of from twenty-five to fifty per cent, chiefly with sulphate of baryta, a cheap and harmless 

 mineral compound. By resorting to practices of this sort dishonest dealers can supply 

 their customers at a less price than the cost of the pure article, and at the same time make 

 large profits. It is a matter of regret that with an Adulteration Act in force, which if 

 properly carried out would at once put an end to these and all such impositions, the public 

 are not better protected. 



The insect enemies of the Potato Beetle are in some localities rapidly increasing in 

 numbers. In the annual report of our Society for the year 1871, our esteemed coadjutor, 

 Mr. E. B. Reed, contributed an excellent article on the Potato Beetle, in which he en- 



