HUNGERFORD: AQUATIC HEMIPTERA. 245 
Corixids Added The first two Corixids added refused to eat the stuff, 
although when placed in 17129A they began feeding promptly enough. 
After the material was cold and had been repeatedly washed, the bugs 
foraged upon it. The stomachs contained very finely divided brown 
matter with no animal remains. In this culture no rotifiers and the like 
had had any chance to develop. The brown grindings, only the finest of 
them, were swept in directly. 
CULTURE 16220 (Alfalfa base culture.) 
History and Diagnosis Doctor Emkody had a large circular aquarium 
in which he had placed ground alfalfa and a little manure. The culture 
had reduced itself to a spongy mass in the bottom and the water was 
fairly clear, with duckmeat growing on top. The plant life is largely 
Oscillatoria, diatoms, etc. present also. 
Corixids Added. Bugs were kept here for more than a month, and 
did very well. Their stomachs were always full of dark green material, 
which often consisted of great skeins of Oscillatoria filaments and little 
else. In some of them this blue-green could be traced from fresh 
material in the fore part of stomach to broken up, disorganized particles 
in rectal pouch. 
CULTURE C. (Bran.) 
History and Diagnosis. Ground-up bran. 
Added Corixids. This experiment was not a success at all. Fer- 
mentation made life untenable for the bugs. 
CULTURE 16221. (Euglenz.) 
History and Diagnosis. A large rectangular aquarium. The bottom 
contained sand and the aquarium had been in use a long time. A green 
growth covered the sides and bottom. The water itself was green, due 
to millions of Euglenids! 
Corixids Added. A great many Corixids were placed here and after- 
wards examined. Their stomachs were packed green with Euglenids and 
little else! 
CULTURE 179. (Largely Mougeotia.) 
History and Diagnosis. A large aquarium jar had been sitting be- 
neath a constantly running tap. It contained quantities of oozy material, 
having a brownish tinge. This consisted of diatoms, Scenedesmus, Gleo- 
eapsa and Mougeotia filaments. The last the dominant organism. 
Corixids Added. Examination of Corixids after feeding here proved 
that they were consistently gathering the Mougeotia after their stomachs 
were packed with it. 
CULTURE 17143. (Mougeotia.) 
History and Diagnosis. Placed sand in the bottom of a large rec- 
tangular glass jar. Added some green material from a jar in Doctor 
Embody’s office. 
Corixids Added. After a couple of weeks added a number of fifth- 
instar nymphs of P. buenoi and some adult A. alternata. After a couple 
of days examined the stomach contents of the bugs. In every case the 
