BELOSTOMA. 39 



Mr. E. E. G-reen {supra) has given some most interesting facts 

 relating to the life-history of this species. From observations 

 made on specimens kept in a large glass aquarium, he observed 

 that they were sluggish creatures and remain during daytime 

 with the tip of the tail projecting above the surface of the 

 water, seldom moving unless disturbed. He w^as of opinion that 

 the natural food of the species is such large insects or small 

 terrestrial animals as fall accidentally into the water ; it will also 

 feed upon frogs when it can catch them. Large horny beetles, 

 such as Orrjctes, and large grasshoppers were also taken. 



Every fresh specimen that Mr. Green examined was infested 

 by a peculiar elongate parasite or water-mite (fam. Hydrachnidse), 

 some species of which attack most water-bugs. 



