Increasing interest in limnology, aquatic biology and related sciences, has been one of the main factors in turning the attention of systematic coleopterists to this family of small beetles. Many new species have been added to the catalogue recently, and it seems probable that there are many more nearctic species yet to be described. It is with the idea of fostering the growing interest in this group that the following notes are offered from an experience of severa1 years' searching for these small, slow-moving, inconspicuous beetles.