FISIZKILLER. One of the great aquatic bugs of the heteropterous family Helostombhe, which prey upon fishes. They are the largest of existing hugs, sonic reaching a length of four inches, and have all oval outline, flat body, and a brownish hue, easily hidden. Their legs are flattened into powerful swimming organs, except the foremost pair, which are ineurved and form organs for seizing and holding their vietims, aided by hooks and proc esses on the inner surface of the tibia. The mouth parts include a strong beak for stabbing the prey, from which all the blood is sucked before it t is let go. At the end of the abdomen are two narrow flattened append ages, which are extensile Litt not concerned in res piration. The family is numerously represented in the rivers and ponds of northern Africa and southern Asia, but most ex tensively in America. The largest known species is Belostoma gra ndis of the Amazonian region, where it lurks on the muddy bottoms of sluggish streams and bayous, ready to seize any salamander, fish, or other aquatic animal that it can overcome.
The two most abundant and largest species in the United States are Belostoma Amerieanum and Benacus grisens, which much resemble one an other in the brown-gray color and shape, but may be distinguished by the fact that the Belostoma "has a double groove on the under side of its fore thighs which is lacking OD the thighs of Benacus." These bugs swarm about electric street lights in such numbers as to be known in many places. of late, as 'electric-light bugs.' They breed and de velop wholly in the water, but their life history is not well known. The females of a related genus, Zaitha, have been found to have the curious habit of depositing and fastening their eggs upon the backs of the males. who unwillingly carry them about until they hatch. Great damage may fol low the introduction of these bugs into fish cultural establishments. Consult Summers, "The True Bugs, or Hetcroptera, of Tennessee," in Tennessee Agricultural Experiment Station Bul letin, col. iv., No. 3 (Nashville', 1891).