2 Journal New York Entomological Society. fVoi. xxv, 



catching and holding prey, have developed along a line quite remote 

 from the usual form. The forelegs possessed by the Mantids and 

 the'Notonectids alike are suited to withstand the struggle, but the 

 spoon-shaped scoops of the forelegs of Corixids, fringed as they are 

 with bristles, might present a sorry sight after an encounter with 

 some struggling victim (Plate II, figs, i, 4 and 5). Perhaps Dr. 

 Kirkaldy^ had this point in mind when he wrote regarding the 

 Corixids : 



"Although not so specially adapted to our eyes for such a life, 

 the Corixidas have gained a more complete mastery over the prob- 

 lems of aquatic existence than their relatives, the Notonectidae and 

 Naucoridse, if we may judge by the much greater number of their 

 species." 



As we shall see, their equipment is more nicely adapted to the lives 

 they lead than we have ever supposed. 



When we began a study of the food habits of the boatmen, aside 

 from the generalization cited at the beginning of this paper, there was 

 but one specific clue as to their food habits. Dr. Abbott noted some 

 of the larger nymphs of Ramphocorixa halanodis (Abbott)^ feeding 

 on ostracods. Our studies were started in the fall, and one Corixid, 

 after a prolonged fast, was induced to attack a blood worm. 



Though the adult Corixids were early noted to spend much time 

 apparently scraping the sediment from the dead oak leaves that were 

 in the aquarium, it was not until spring that the nature of their feed- 

 ing' habits was definitely determined. This was revealed in a delight- 

 ful way by the newly hatched Corixids, which were confined in petrie 

 dishes with a little pond water, and some of the brownish deposits, 

 so characteristic of the bottom of quiet pools. These little fellows 

 could be observed for hours under the binocular and were not easily 

 disturbed. 



The method of food getting by boatmen in all stages has been ob- 

 served many, many times, but the account would not differ greatly 

 from my first observation, recorded in my notes as follows : 



" Petrie dish A'.liis my good fortune this morning to watch under 

 the binocular one of these little corixid nymphs search out his break- 

 fast. It is on a bit of oak leaf covered over with brown sedimentary 



3 Canadian Entomologist, Vol. XL, No. 4, 1908. 

 4 Now acumitiata Uhler. 



