16 



ently in a healthy condition, for the purpose of rearing them ; these were placed in two 

 separate boxes with a liberal supply of food ; within twenty-four hours a large number of 

 them died, all apparently from this disease ; they were frequently examined, the diseased 

 and dead were separated from the living, but within three days only four remained alive ; 

 of these four only one survived to enter the chrysalis state, and this one did not mature 

 the perfect insect, hence I am indebted to Mr. James Fletcher for the determination of 

 the insect, who, being on the spot, succeeded in rearing several specimens of the motb. 



A few days later complaints were made to me of the depredations of the caterpillar 

 of another of our cut-worms, a species usually very common, the larva of a moth known 

 to entomologists as Hadena arctica, which was very destructive to corn and other crops, 

 A few days sufficed to mature the swarms of both these devastating armies, Avhen these 

 caterpillars, which had escape;! both disease and enemies, buried themselves in the ground 

 and changed to chrysalids which subsequently produced the winged moths. 



Every season these cut-worms are a source of great annoyance to gardeners and farm- 

 ers who find their young corn, cabbage, tomatoes, melons and other plants of succulent 

 growth suddenly cut down by an unseen enemy and withered. Stalks of wheat and other 

 grain are often cut in a similar manner by the same enemies, and they being universally 

 distributed and extremely voracious, inflict enormous losses every year. They have re- 

 ceived the name of cut-worms from their habit of cutting off near the base tender and 

 succulent plants, and under this common designation there are included a number of specie? 

 having similar habits, belonging chiefly to the genera Agrotis, Hadena, and Mamestra, 

 some of which possess striking points of difference in the moth state, although they much 

 resemble each other while in the caterpillar condition. The general history of these cut- 

 worms can be given in a few words : The eggs are laid by the parei|t moths during the 

 latter part of the summer, sometimes on the ground about the roots of grass and other' 

 plants, and sometimes on the leaves near the ground. Within two or three weeks young 

 larvae hatch from these eggs and by the time autumn sets in the caterpillars have attained 

 the length of half an inch or more, when they burrow into the ground deep enough to pro- 

 tect them from injur}' by severe frost, and there remain in a torpid condition all the winter. 

 The warmth of spring arouses them to activity, when they seek the surface of the ground 

 feeding at night on almost any green thing they meet with, eating with apparently 

 insatiable appetite as they approach maturity, and burying themselves during the day 

 under the surface of the ground in the neighborhood of their depredations. When full 

 grown they burrow in the earth to varying depths, and there change to chrysalids from 

 which the mature insects escape in two or three weeks. 



These insects are hurtful only while in the larval condition. As remedies, showering 

 the plants with Paris Green and water, sprinkling them with air-slacked lime or powdered 

 hellebore, or strewing lime or soot, or mixtures of these substances around the plants on 

 the surface of the ground have all been recommended and in some cases have been found 

 useful. Plants have also been protected from injury by these caterpillars by strewing around 

 them a little dry sand impregnated with coal oil, in the proportion of a teacupf ul of coal 

 oil to a pailful of sand thoroughly mixed : the application should be renewed every week. 

 This method of warding off the attacks of injurious insects by the use of odorous sub- 

 stances repugnant to them is rapidly growing in favour on account of the success attending 

 its use. This coal oil remedy for cut-worms is said to be Aery effectual, and the cost of the 

 application being so trifling its usefulness should be extensively tested. ' It is manifest 

 that none of these measures are feasible where field crops are invaded, as the area would be 

 too great for any one to undertake to cover with such material. In such cases nature has 

 provided efficient remedies to reduce their numbers. Besides the disease to which I have 

 referred, there are armies of parasitic insects which prey on them. Some of these directly 

 devour their living prey, others deposit eggs within the bodies of their victims, which, 

 hatching into grubs, consume them. Hence it often occurs that an insect which is 

 abundant one season is scarce the next. 



These cut-worms are very widely disseminated. Early in July I received specimens 

 from Manitoba from the Deputy Minister of Agriculture, of a caterpillar belonging to 

 this group, which was found to be seriously injuring vegetables, and in some localit'es- 



