In this calendar I propose to especially notice the injurious insects. References to the times of their appearance must be necessarily vague, and apply only, in a very general way, to the Northern States. Insects appear in Texas about six weeks earlier than in Virginia, in the Middle States six weeks earlier than in northern New England and the North-western States, and in New England about six weeks earlier than in Labrador. The time of the appearance of insects corresponds to the time of the flowering or leafing out of certain trees and herbs; for instance, the larvae of the American Tent caterpillar and of the Canker worm hatch just as the apple tree begins to leaf out; a little later the Plant lice appear, to feast on the tender leaves; and when, during the first week in June, our forests and orchards are fully leafed out, hosts of insects are marshalled to ravage and devour their foliage. _The Insects of Early Spring._ In April the gardener should scrape and wash thoroughly all his fruit trees, so as to rub off the eggs of the bark lice which hatch out early in May. Many injurious caterpillars and insects of all kinds winter under loose pieces of bark, or under matting and straw at the base of the trees. Search should also be made for the eggs of the Canker worm and the American Tent caterpillar, which last are laid in bunches half an inch long on the terminal shoots of many of our fruit trees. A little labor spent in this way will save many dollars' worth of fruit. The "castings" of the Apple Tree Borer (Saperda bivittata) should be looked for at the base of the tree, and its ravages be promptly arrested. Its presence can also be detected, it is said, by the dark appearance of the bark, where the grub is at work: cut in and pull out the young grub. It is the best time of the year to catch and kill this pest. Cylindrical bark borers, which are little round, black, weevil-like beetles, often causing "fire-blight" in pears, etc., are now flying about fruit trees to lay their eggs; and many other weevils and boring beetles, especially the Pea weevil (Bruchus pisi, Fig. 215), the Pine weevil (Pissodes strobi, Fig. 216), and Hylobius pales and Hylurgus terebrans, also infesting the pine, now abound, and the collector can obtain many specimens not met with at other times. [Illustration: 215. Pea Weevil and Maggot.] [Illustration: 216 Pine Weevil and Young.] The housewife must now guard against the intrusion of Clothes moths (Tinea), while many other species of minute moths (Tineids) and of Leaf-rollers (Tortricidae) will be flying about orchards and gardens just as the buds are beginning to unfold; especially the Coddling moth (Carpocapsa pomonella). On warm days myriads of these and other insects may be seen filling the air; it is the busiest time of their lives, as all are on errands of love to their kind, but of mischief to the agriculturist.