246 
Sidney I. Kornhauser 
Eecently Montgohiery (’ll) has brought together in a more de- 
tailed 'way bis results obtained from the study of Euschistus. He follo’ws 
the entire bistory of tbe cbromosomes and tbe cytoplasmic structures. 
He Claims parasyndesis witb prereduction for tbis insect. 
III. Material and Methods. 
Enchenopa curvata was obtained in large numbers eitber by “swecp- 
ing” in meadows containing clover and golden rod, or merely by picking 
tbe insects from tbe individual plants. Tbe insects were transported to tbe 
laboratory, and a supply was kept on band in several large insect cages 
containing potted clover plants. Tbe cages were kept in the sunlight. 
The insects lived very weU, mated, and layed eggs in large numbers, 
deep in the tissue of the clover stems. Nyinphs before tbe final moult 
(Plate XVIII, Figs. 3, 4) were obtained in June. These are remarkable 
in sbowing no external sexual dimorphisni, the abdomen ending in a 
tube of telescoping segments, a striking difference to tbat of the adult 
female, for instance, witb her weU fornied ovipositor for piercing tbe 
stems (Plate XVIII, Fig. 6, middle row, tbird individual from the left). 
These nympbs do not have tbe sex glands well developed, and it is better 
to obtain material from adults. Adult males appeai’ earlier in June than 
the females and show numerous spermatogonial and sperinatocyte divi- 
sions. A little later tbey also contain mature spermatozoa. Tbe females 
sbortly after tbe last moult have very smaU ovaries, wbicb increase 
greatly in size later in the season, untü tbey fül the abdomen almost 
completely. Males become very scarce in August, wbereas the females 
live longer and lay best during tbat montb. Tbe absence of males is 
accounted for by tbe fact tbat copulation takes place before the females 
have produced mature eggs, the spermatozoa living for some time in tbe 
spermatbeca. 
Considerable numbers of E, Unotata were obtained in Pittsbmgb 
and in Gold Spring Harbor feeding on the locust, Robinia pseudacacia L. 
These were kept aüve near the laboratory by enclosing them in large 
cylinders of absorbent cbeese cloth slipped over brancbes of small locusts 
and closed at the ends by cords tied witb bow knots. Tbe insects Uved 
weU, mated, and layed eggs. In E. binotaia, tbe laying season lasts into 
late September. 
The Same methods of preservation and staining were used in botb 
species. In addition to E. curvata and E. binotata, I also obtained material 
of the large membracid Thelia bimaculata (Fahr.), and of tbe fulgorid 
