199 
if adult, it will undoubtedly form a new genus in the family. We hope 
Mr. Zabriskie will be able to obtain more material. The specimen was 
captured in July, 1890, in the stream of the waterworks at Flatbush. 
The color is blackish with sundry whitish spots visible from above; one covering 
the middle of the prothorax extending on to the hind margin of the head; two on 
the mesothorax; a lateral row on each of the first seven abdominal joints, at the 
base of the middle cox, posterior coxe, base of the trochanters and base of the 
first joint of the antenne. The antenne (not palpi, as Mr. Zabriskie describes) are 
the most striking peculiarity of the insect. They are four-jointed and are evidently 
prehensile or raptatorial. The basal joint is stout, nearly as long as the third and 
Fic. 22.—Undetermined Hydrobatid Water-bug: a, dorsal view; b, ventral view—greatly enlarged; 
¢, antenna from above; d, same from below—still more enlarged (original). 
fourth together, bulging near the middle, and furnished with a tuft of hairs or 
bristles abruptly cut off, and a few straggling bristles and longer and finer hairs at 
the sides. Joint 2 is small, with a curved spine near the nether base; joint 3 
elbowed, dilated distally and beneath, with a pale hyaline disk or cushion sur- 
rounded by a few stiff hairs; terminal joint ending in a hook with a stout prong 
about the middle. 
The beak is short and stout, reaching to the base of the prosternum. The eyes 
are large and globular, and there are two minute ocelli. The front legs are short 
and robust, the tarsi two-jointed, the basal joint almost hidden, and the terminal 
joint prolonged into a hook and having a claw attached at its base. Middle legs 
ype 
