THE CANADIAN ENTOMOLOGIST. 129 



illustrated and carefully prepared bulletin has been issued by Mr. M. V. 

 Slingerland, of Cornell University Agricultural Experiment Station, in 

 which the life history of this most interesting but very serious enemy of 

 the fruit grower is fully described. The above illustration, kindly lent by 

 the editor of the Canadian Horticulturist, is copied from that bulletin. 



The localities in Canada where this little pest has been most injurious 

 are situated along the northern shore of Lake Ontario and the St. 

 Lawrence. Dr. Young, of Adolphustown, in whose orchard of Duchess 

 of Oldenburgh and Russet apples the first important occurrence of this 

 insect as an apple pest was observed, states that they were first noticed 

 in his orchard about 1885. Reports of its ravages have also been 

 received from Oshawa, Port Hope, and Maitland, Out., in all of which 

 places it had an appreciable effect on the yield of the orchards. 



The life history may be summarized as follows : The eggs, which 

 are described by Mr, Slingerland as beautiful objects, are of a delicate 

 light lemon-yellow colour, deeply pitted with triangular depressions sepa- 

 rated by narrow ridges. They are very minute, and are deposited by the 

 females among the hairs of the new shoots and on the under sides of the 

 youngest leaves. The egg stage lasts about two weeks, the little cater- 

 pillars emerging in the latter half of July. For the first period of their 

 lives they are miners feeding on the inner tissues of the leaves. After 

 two or three weeks they make small, rather flat and elongated, curved 

 cases, in which they pass the winter. These cases, inside which they live 

 and which they carry about with them, are made of pieces of the upper and 

 lower skins of the mined part of the leaf, lined inside with silk. The two 

 surfaces of the leaf are easily recognizable on the cases from the pubescence 

 of that side which was taken from the lower surface. Soon after making 

 these winter cases, the caterpillars, now about a quarter grown, migrate to 

 the twigs of the tree and fasten themselves securely to the bark. In 

 badly infested orchards they are sometimes found clustered in hundreds 

 around the fruit spurs. 



As soon as growth begins the following year, about the beginning of 

 May, the case-bearers crawl out to the opening buds, and at this time 



