The subfamily Archipinae, as represented in North America, comprises a group of 72 described species of moths, varying in wing expanse from one-half of an inch to one inch. In several species, the costal margin of each forewing is sinuous, and when the moth is resting, its outline roughly corresponds to that of a bell. Hence, these moths are sometimes referred to as the bell moths. The larvae feed on the foliage of many species of coniferous and deciduous plants; and as they feed, they bind, crumple, or roll the leaves together to form a shelter. From this habit the larvae are commonly called leaf rollers or leaf tiers, and they often occur abundantly enough to cause considerable injury to plants of economic value. The most destructive of these at the present time are the spruce budworm, Choristoneura fumiferana Clem. and a closely allied species, C. pinus Free.. the jack-pine budworm. Both of these species present a major control problem to those interested in the preservation of the spruce, balsam, and jack-pine stands of the forested regions. The defoliation of individual trees, and of large stands, is often so severe that it causes the death of numerous trees. This results in a loss of valuable timber, provides situations for other insects and plant diseases to develop, and increases the fire hazard in the forested regions.
No satisfactory classification of this group of moths has been presented in the past, and in consequence the identification of the various species, as well as the establishment of their relationship to one another, was difficult and often impossible. The purpose of this study is to present a classification based on the external anatomical structures of the adults, supplemented with all available biological data, including food plants, ecology, and geographical distribution.
An ideal classification would include a systematic arrangement of the immature stages, but in this group the food plants and the larvae of many species are unknown. Therefore, such a classification is not practical until more adequate knowledge is available. There is, however, on the basis of the few larvae and pupae available, an indication that the setal arrangement of the larvae, the shape of the cremaster and the spining of the pupae may form a basis for the identification of species groups.