96 THE UNIVERSITY SCIENCE BULLETIN. 
four eggs; on the 6th, 11 eggs, on the 7th, 17 eggs. By August 31 this 
unfertilized female had laid 47 eggs. These eggs were left under the 
observation of a friend to determine whether any would hatch. They 
were forgotten. In the case cited above where 8 females and 1 male were 
placed, the male escaped July 18, but the females continued to lay fertile 
eggs. Ina third jar an egg hatched July 138. An adult female came forth 
July 25. Placed a male with her and by August 4 there were 28 eggs, 
which were removed. They were mating on this date. The evening of 
August 5 there were 11 eggs. All of these were placed at the water line. 
August 14, 78 eggs were removed. This one female in 10 days laid 78 
eggs. The male died on the 22nd, and the rearing discontinued on 
August 31,.when 67 more eggs were removed—a total of 173 eggs in 
‘about 36 days. The female was lively at the time the observations were 
stopped. Thus it will be seen that these bugs lay many eggs and are 
capable of laying as many as 11 in 24 hours. 
Longevity. The adults live a full season and no doubt longer. More 
data on the longevity of the water bugs is to be desired. 
Food Habits. Kirby, 1892, made the unfortunate statement that their 
“habits were probably herbivorous.” A little patient observation would 
have dispelled such a notion. The measured deliberation of these insects 
in their undisturbed movements is not conducive to a quick determination 
of their habits. One summer the writer made the practice of spending a 
few hours each day in the observation of the normal activities of the bug 
population of the pool. A three-foot “two by four” with a piece of board 
nailed on one end, served as a stool that could be carried about in the 
shallow waters and made quiet and continued observation possible. 
It is only in such a way that one can make satisfactory notes upon these 
insects. 
As stated by writers from the beginning, these bugs are carnivorous. ~ 
Kirkaldy was puzzled to note that the fore limbs were not modified for 
the prehension of their prey, but the writer has shown that the strong 
and retrorsely barbed stylets are quite sufficient for the retention of their 
victim. This same morning several were seen with newly emerged and 
still white midges. He found that the source of their food supply in the 
main comes from organisms beneath the surface. Ostracods at the sur- 
face film, mosquito wrigglers and pupa, and even Corixid nymphs have 
been speared out of the water. Bueno noticed aquarium specimens put- 
ting out their hairlike rostra and penetrating the surface film with them. 
A closer study of this would have lead him to some interesting observa- 
tions. In the field, the early morning is a splendid time to watch them. 
On one pool where they were living upon a floating mass of dead cattail — 
leaves they were frequently observed. We offered them mosquitoes, but 
although they might fall within a centimeter of them, they might investi- 
gate indifferently but promptly turn their attention to the things that were 
taking place at the surface film. For the activity here they were all at- 
tention! In one case a third instar N. wndulata came to the surface 
near an adult female. She dipped her rostrum and antennz and stealthily 
approached. Would she hook into this creature? It surely would capsize 
her for she was upon open water. Now a moment’s survey with the beak 
; 
5 
t 
: 
; 
é 
