With Canada's extensive system of rivers and lakes, it hardly comes as a surprise that the order Trichoptera is well represented in this country. This book, translated from French, is a revised and updated English edition of the Genera des Trichopteres du Canada et des etats adjacents, originally published in 1980. The classification of several taxa of Trichoptera is currently in a period of change and instability. The author's goal was to provide a synopsis of all Canadian supraspecific taxa, i.e., suborders, families, subfamilies, genera, and subgenera. The geographic region under consideration extends beyond the boundaries of Canada and includes all the adjoining American States and Alaska.

This work has been written for both practical and scientific purposes. It is intended not only for the Trichoptera specialist but also for the amateur. The layman will find clear, concise descriptions that are accompanied by a number of figures illustrating most of the characters mentioned and by complete dichotomous keys. Each genus is represented by one of its most common species, with illustrations of the venation and genitalia in both sexes. Descriptions do not apply to all known taxa but only to the species occurring in our area. The few taxonomic discussions that occur throughout the text have been kept to a minimum and can be easily disregarded. To permit identification down to the species level, wherever possible within a genus, names have been provided for all the species belonging to genera containing fewer than five species. In addition, a few distinguishing characters not requiring illustration have been included. Likewise, revisions are mentioned where appropriate.

With the professional in mind, systematic descriptions are provided. All the main characters of the taxa are given and illustrated as they define these taxa, even if they are not immediately useful for purposes of identification. Thus, occasional neoformations of the legs, palpi, and antennae have been illustrated. The author described and often figured the abdominal hemogill system and the internal gland of sternite V, wherever present. Also, more importantly, he elucidated the morphology of the genital segments and established the identity and homologies of most of the appendages in all families and genera, and this with a degree of certainty that naturally may not be absolute but that he generally consider satisfactory (except in the case of the Hydroptilidae). For this purpose he relied on Nielsen's work on the subject (1957).