The small species of Belostoma (Heteroptera: Belostomatidae): revision of plebejum group.

Nieser gathered the water bug species included by Lauck in the groups Belostoma pygmeum and Belostoma plebejum in a single group, Belostoma plebejum. We follow this criterion and use the terminology used by EstCvez and Polhemus for species descriptions. The Belostoma plebejum group includes seven small species with the ventral diverticulum of male genitalia recurved ventrad: Belostoma lariversi De Carlo, 1969; B.

A rocking motion sensor for the blind.

Rocking motion is an unconscious and often unwanted phenomenon exhibited by the blind. It is usually manifested in oscillatory back and forth, side to side, or rotatory movements of the upper torso or head at about 1 Hz rate. Subjects desiring to function unobtrusively in the world of the sighted need to be alerted when rocking so they can control it.