4 
150 THE UNIVERSITY SCIENCE BULLETIN, 
Color. Newly laid, pale, grayish green, the outer end of egg blotched 
with patches of darker color due to a trace of brown. The surface 
minutely and irregularly hexagonally reticulate, not plainly visible even 
under low power binocular, but becomes apparent under low power com- 
pound. A bit of the chorion mounted on a slide and examined by trans- 
mitted light shows a series of irregular hexagonal figures of various 
sizes. The boundaries of the figures appearing as a tracery of fine white 
or transparent lines on a brown ground. The egg clusters are held 
together and to their support by irregularly globose masses of gelatinous 
like material. See plate XVII. 
Summary. These giant water bugs, distinguishable by the presence 
of a groove in fore femora, are fiercely predaceous creatures of our 
larger ponds. In their nocturnal migrations from one body of water to 
another they are frequently attracted to the lights. The eggs of L. 
americanus and of L. uhleri are now known. In nature they are laid on 
reeds above the surface of the water. Nothing is known about the length 
of the various stages. 
Genus BENACUS. Stal. 1861. 
There is the one species in this country, B. griseus Say. It is the larg- 
est of our electric-light bugs. It differs from Lethocerus in having less 
thickened fore femora which are not grooved to receive the tibize when 
flexed. 
The biological notes of any extent (aside from collecting) consist of 
two papers; one by Brimley, Hnt. News, 1905, describing the walking of 
B. griseus, and the other by Needham, Ent. News, 1907. This second 
paper is a splendid paper, accompanied by remarkably clear photographs 
of the egg cluster, hatching eggs, newly emerged nymph and adult. 
Oviposition. Weed, 1897, tells us eggs are laid in masses on sticks 
and other rubbish at margin of ponds. Needham, 1907, says that “the 
egg clusters are two or three inches long, and contain 75 to 100 eggs of 
a size that for insects is fairly immense. The eggs are attached by one 
end in more or less regular rows, and they cover in a single layer the 
broader, flatter side of the stem. They would be conspicuous but for their 
resemblance in color to the stem.” The longitudinal streaking of brown 
upon a lighter ground, together with the way they are placed and spaced, 
makes them fall into line with the flutings of the stem, and greatly as- 
sist in the concealment of the cluster. The egg clusters are attached 
above the water line. 
The Egg. 
(Description from Needham.) 
Size. 5 mm. long; 2 mm. in greatest diameter. 
Shape. Oblong oval in form with very obtuse ends. 
Color. Each egg is marked longitudinally with 20 or more irregular 
stripes of brown (often interrupted, cleft, fenestrate, or anastomosing, 
and always with uneven margins) convergent toward the center of the 
free end upon the upper side. Under a lens the eggs remind one of a 
pile of Georgia watermelons. If the color were green instead of brown 
: 
