North American spiders of the genera cybaeus and cybaeina

The frequency with which members of the Agelenid genus Cybaeus appeared in collections made by the authors in the mountainous and timbered sections of the Pacific coast region and the representations therein of various apparently undescribed species led to the preparation of this review of the known North American forms. One species heretofore placed in Cybaeus is made the type of a new genus Cybaeina. Most of our species occur in the western states; and it is probable that further collecting in this region will bring to light a considerable number of additional forms.