2 ENTOMOLOGICAL NEWS. [Jan., 'o6 



tim), the third pair of pedes only are natatorial and the tibiae 

 and tarsi are heavily fringed with long hairs. The legs are 

 moved simultaneously and quite rapidly in powerful backward 

 strokes, the fringing ciliae expanding on the propulsive and 

 closing on the return stroke. Plea agrees with the larger 

 Notonectids in the position and method, but the stroke is 

 quicker and more clipping and the tibiae and tarsi are very 

 sparingly provided with short hairs. On land, both Notonecta 

 and Buenoa move very awkwardly. When first put on any 

 surface they jump about and move the third pair of legs des- 

 perately with the swimming motion, but as soon as they get 

 their bearings, they begin to crawl rather slowly and painfully 

 by means of the first and second pairs of pedes. Plea, on the 

 other hand, can very frequently be seen creeping among the 

 water plants in which it hides, and at other times it moves 

 along the surface film, actually walking suspended from it, 

 back down of course. On land it walks, using all three pairs 

 of pedes. 



Corixa swims using both the pedes of the third pair simul- 

 taneously, as in Notonecta, and the position in the water is 

 back up. On land, it jumps and skips about, the first and 

 third pairs of legs being quite specialized and only the second 

 ambulatorial, which naturally prevents the bug from walking. 



In the Belostomatidce I have been unable to make fresh ob- 

 servations on Benacus and Amorgius (=Belostoma, olim), but 

 having had a number of Belostoma (Zailna) fluminea in my 

 aquaria at various times, I have been able to study this last 

 species with care and to repeat my observations several times. 

 Be?iacus I have never seen in the water. Of Amorgius obscurum 

 Dufour I have had several nymphs which were brought to 

 maturity. My recollection is that they move the hind legs 

 together in swimming, confirming Mr. Brimley's observation 

 on Benacus. On land they scuffle along pretty rapidly. With 

 regard to Belostoma fluminea Say to confirm previous observa- 

 tions, I confined a bred specimen in a glass dish so small that 

 while it could move its legs freely, it was not able to stir from 

 under my magnifier, no matter how furiously it might paddle. 

 It was then stirred up, and its motions could be observed 



