A revision of the species of the genus Trichobius

Abstract

This paper deals with the species of the commonest genus of the American Streblidae. The descriptions of the species were made from specimens mounted on slides, in Canada balsam. Here I wish to point out again that spirit preserved specimens are unsuitable for the study of these Diptera. These specimens do not show clearly the details of the structure of some sclerotized parts, and especially the arrangement of the small setae on the thorax, which in some cases, are the only reliable characters for the separation of the species. The study of unmounted specimens of these Diptera may easily lead to incorrect identification, or to the increase of undesirable synonyms.