232 Journal New York Entomological Society. [Voi. x. 



Venter abdominis without a keel ; connexiviim sparsely ciliated. 

 Color throus^liout bruno-testaceous, rangint^ in shade. Length, 2-2.4 mni' ". 

 width, 1.I-I.2 mm. ; height, 1.3 mm. 



I'his interesting little species I first found in Van Cortlandt Park, 

 on SepteiTiber 13 of this year. I discovered it in washing the copious 

 rootlets of a species of Duckweed, and took it at first to be a very 

 large Daplinia. On looking more closely, I saw it assume the typical 

 notonectid position, abdomen up, its extremity at the surface. Later 

 in the season, toward the end of October, in company with Mr. W. 

 T. Davis, we found it in Cape Henlopen Pond in Staten Island. 



Two of the Pleas are now living in a covered glass with some 

 Nifclla to aerate the water, together with an agrionid nymph and an 

 ephemerid nymph. To feed them there are plenty of water fleas. I 

 have not seen the Pleas eat these, nor is their number apjjarently 

 diminished, and from observations I am inclined to believe that they 

 are vegetable feeders. I cannot, however, assert positively the nature 

 of their food. Their favorite position seems to be clinging to the 

 underside of the duckweed leaves. They rarely swim, apparently pre- 

 ferring to creep along the stems of the aquatic plants, on which at 

 times they rest, clasping them with the legs. When they do swim, 

 they move through the water by means of a rather rapid, clipping stroke. 



When living and seen in the water, by means of a one-half-inch 

 lens, the hairs arising from the punctures on the hemelytra, can be 

 seen standing out ray-like, the punctures themselves being noticeable. 

 Because of the highly convex; dorsum, homogeneous character of the 

 hemelytra and their habit of creeping along the stems of the water- 

 plants, they might at a cursory glance be taken for small aquatic beetles. 



Those I have collected were found along the edges, among the fine 

 roots of the grasses and the stems of the netted water weeds, and from 

 the habit of creeping noted, it might seem that this is their favorite 

 ihabitat. 



The places mentioned are the only localities for it that I know of 

 in this vicinity, but Plea should be found anywhere. Uhler in his 

 " Check List " gives this species as being found in the United States. 

 Probably it is not oftener collected on account of its inconspicuous 

 size and retiring habits. 



Notonecta insulata Kby. 



" Head : notocephalic lateral margins fairly straight and nearly parallel, very 

 slightly constricted near the base ; vertex little wider than synthlipsis, which is about 



