22 4 REPORT OF NEW JERSEY STATE MUSEUM. 
G. affinis Aube. Anglesea (Rob); Staten Island (Coll); “New Jersey” 
(U M). 
G. pernitidus Lee. Lakeburst (Rob). 
G. analis Say. Spring Lake (Ch); Hammonton VIII (Dke); Atlantic Co. 
(div); Lahaway V, 28, (Coll); Clementon VII, 26, Atco IX 2 27 
(GG). 
G. marinus Gyll. Anglesea (Rob). 
G. opacus Sahib. Spotswood (Rob). 
G. gibber Lee. Spotswood (Rob). 
G. borealis Aube. Madison (Pr); Hammonton VIII (Dke); Atlantic Co. 
(div); Lahaway V, 28, Jamesburg (Coll). 
G. lugens Lee. Boonton VI, 12 (GG); Spotswood (Rob); Atco (Li). 
G. picipes Aube. Spotswood, Lakehurst (Rob); Atco IX, 27 (GG). 
DINEUTES MacL. 
D. vittatus Germ. New Brunswick and southward April to midsummer, 
everywhere, singly in ditches and small streams; never in ponds. 
D. emarginatus Say. Westville (Rob); DaCosta, Jamesburg VIII, 24 
(Coll); Merchantville VI, 5, Clementon VII, 26 (GG). 
D. hornii Rob. Budd’s Lake IX, 3 (Coll); Boonton V, 19 (GG); New 
Brunswick (Rob); Westville (Dke); Staten Island VIII, 16 (Ds). 
D. nigrior Rob. Budd’s Lake IX, 3, Newark, New Brunswick, Lahaway 
(Coll); Spotswood, Lakehurst (Rob); Boonton V, 17, Woodbury VI, 
8, Clementon VII, 26 (GG). 
D. assimilis Aube, Common throughout the State nearly all summer. 
D. discolor Aube. With the preceding and equally abundant. 
D. carolinus Lee. Hammonton VIII (Dke). 
Family HYDROPHILIDiE. 
These are the “water scavengers,” usually black in color, sometimes 
with yellpw, orange or red markings along the margins, usually smooth, 
polished and very convex above, flattened below. The antennae are short 
and clubbed or enlarged at tip; hence the species are easily distinguish¬ 
able from the divers, which have them, filiform or thread-like. A number 
of the smaller species are different in form and have the surface rough or 
pitted; these crawl rather than swim on the soil and vegetation under 
water. Finally there are yet other species structurally like those inhab¬ 
iting the water, that live in moist earth, dung and decaying or fermenting 
vegetation. They are of no economic importance. As in the other water 
beetles, Mr. Roberts has helped out in this family. 
HELOPHORUS Fab. 
H. lacustris Dec. Locally common throughout the State all season. 
H. lineatus Say. Madison (Pr); Ft. Lee V (Bt)j Newark (Soc); Wood- 
