SYSTEMATIC AND MORPHOLOGICAL NOTES ON NORTH AMERICAN CONOTYLOID DIPLOPODA

Since the publication in 1895 of the excellent monograph on North American chordeumoids by 0. F. Cook and G. N. Collins, very little basically useful work on our fauna has appeared. In 1895 the number of known species was 27, distributed among ten genera, whereas the most recent listing (Chamberlin and Hoff man, 1958) shows that the total has increased to 86 species and 26 genera, now allocated to nine different families. Yet this in crease is due entirely to papers in which new forms are described with an absolute minimum of attention to detail, the descriptions sometimes being adequate for later recognition of species but not for an understanding of their structure and relationships. To the best of my knowledge only one attempt has ever been made to provide keys for identification of the rising number of species (Loomis, 1943). Upon recently having occasion to work with chordeumoids, I was astonished at the taxonomic condition of Nearctic forms in comparision with the detailed knowledge of European species. Putting our fauna in a more satisfactory position is obviously a large order, and for many reasons a task which can best be ac complished by cooperative efforts. Since a complete revision of the group, however desirable, must still be far in the future, two immediate measures can be undertaken. First would be a drastic improvement in the quality of descriptions and particularly of illustrations; second, piecemeal attacks on various genera or groups of genera as material becomes available. I am concerned at the present with a number of genera that