AQUATIC INSECTS OF FRESHWATER 



FIG. 201. Giant Water-bug, 



Zaitha fiuminea. f&niale with 



eggs on her back. 



houses for sheets of water. Lamps and electric 

 lights also attract them in numbers. They deposit 

 the eggs in masses under logs and stones on the 

 borders of ponds and ditches. The young are 

 predaceous and feed upon small snails and other 

 living creatures and differ but little In appearance 

 from the adults, except in the absence of wings. 

 They reach maturity during the first year. Living 

 prey only is acceptable to both the larva and bug and 

 in attacking smaller fishes they seize them with the fore 

 legs, pierce them with the proboscis, which forms a 



sucking tube, and extract the blood but do not eat the animal. Some of 

 the species of Zaitha attack the spawn of fishes. Of this genus the 



most common in the Eastern section of the United 

 States is Z. fiuminea., which reaches a length of i to 

 I ^ inches. Figs. 201 and 202. The females of all 

 three genera deposit the eggs on their backs which 

 are often entirely covered by nicely arranged trans- 

 verse rows of from 60 to 200 elongate-ovate dark 

 grey eggs deposited by means of a protrusile ovi- 

 positor which can be extended over the back. The 

 Giant Water-bugs and their larvae are among the 

 most destructive enemies of the young of the goldfish and other freshwater 

 fishes, which are often introduced into the hatching troughs as eggs or in 

 the larval stage. Some adults reach the tanks in their nuptual flights. 



Creeping Water-Bugs belong to the Naucoridae, a small family of 

 flat-bodied oval-shaped bugs, having the anterior legs developed to seize 

 their prey and the middle and posterior legs 

 for creeping over the bottom of ponds and 

 water ways. All the species are predaceous but 



confine their attacks 

 more generally to in- 

 sects and their larvae. 

 Pilocoris femarata and 

 Ambrysus signoretti. 

 Fig. 203, are the prin- 

 cipally distributed Atlantic Coast and Western 

 species. They are both of small size, rarely over 

 ^ inch in length and of a reddish-brown color. 

 Toad-Bugs belong to the family of Galgul- 

 idae, and inhabit the muddy margins of ponds, 



fig. 202. Giant Water-bug, 

 Zaitha fiuminea. Male. 



FIG. 203. Creeping Water-bug, 

 Amhrysu! signoretii. Enlarged. 



FIG. 204. Toad-bug, Pelogonus 

 amc' icartus. Enlarged. 



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