HUNGERFORD: AQUATIC HEMIPTERA. 119 



Hibernation. "As ova and no adults could be found in early spring, 

 the winter is probably spent as an egg." 



Mating. Found mating in October. "Many of the pairs remained 

 almost constantly 'in coitu' for several days." 



Number of Instars. Five (?). Takes about 50 days from hatching to 

 adult. 



Food Habits. Eat small insects that fall into the water. Do not dis- 

 dain food that has been dead some time. 



DESCRIPTION OF STAGES. 



The Egg. 

 Three times as long as wide; dirty greenish yellow in color. 



Genus METROBATES. 

 Metrobates hesperiiis. 

 Habitat. This bug is lacustrine. Bueno says it "may be seen con- 

 gregated in large patches of blackness on the smooth waters of our 

 lakes or perhaps in the wide reaches of slow moving streams. Little 

 else is known about this insect. 



Genus TREPOBATES. 

 Trepobates pictus. 



Habitat. This is a beautiful species, as its name would indicate. It 

 is wide spread, and quite usually apterous. Here in Kansas, however, 

 it frequents our ponds and is quite largely winged as taken in the spring. 



Hibe7-nxition. From the collecting it would be assumed it winters as 

 an adult. 



Oviposition. The writer shows some figures of the egg masses of 

 this species. They are laid in solid masses of gelatinous material on the 

 under side of leaves and sticks in the water. The writer has found 

 them under the leaves of Duckmeat and grass blades. The eggs are 

 placed side by side and imbedded in a pad or matrix of yellowish white 

 gelatin. There are from 3 to 10 eggs in a mass. (See plate XII.) 



Incubation. From eggs laid in the laboratory June 19, young nymphs 

 appeared June 24, a period of 5 days. 



Hatching. Before hatching the eggs became beautifully marked with 

 red spots, the large eye spots and sixteen other small dots, distributed as 

 shown in the drawing on plate XV. These spots are located in various 

 places on the nymphs, such as antennae and joints of the limbs. The 

 postnatal molt bears a black shiny "egg burster" like the Gerris. After 

 hatching the nymphs swim about in the water by means of middle legs. 

 They stand several hours of submergence at this time. 



Food Habits. Source of food much as for their larger relatives. 



DESCRIPTION OF STAGES. 



The Egg. 

 Size. .99 mm. long; .312 mm. wide. • 

 Shape. Elongate oval; anterior end more pointed. 

 Color. White, turning to amber; marked with red spots before hatch- 

 ing. (See pi. XV, fig. 13.) 



