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MISSES K. FOOT AND E. C. STROBELL : RESULTS OF 



in our laboratory, aiming to learn to raise these bugs with as low a death-rate 

 as possible, and it was not until after three years of experimenting that we 

 felt it would be safe to attempt to cross two or more of these species. The 

 three most troublesome problems in this work were to provide the proper food, 

 to use cages well adapted for cleanliness and observation, and to maintain the 

 right degree of moisture. The bugs must have not only abundant food, but 

 it must be fresh and clean, and these conditions can be successfully met only 

 by frequently transferring the insects to clean cages with fresh food. This 

 should be done at least every third day, or, better still, every second day. 

 We were forced to do this work ourselves, for raising the nymphs demands 

 such delicate care that we were unable to entrust it to an assistant. It 

 proved to be an arduous task during part of the breeding season, when, in 

 our experimcmts, we found it necessary to change the food for more than 

 30 cages each day. 



The cages we used for the adult bugs were olass dishes about 6 inches in 

 diameter and 3 inches deep. The covers were of coarse brass wire mesh, 

 carefully designed to prevent the possibility of the tarsi of the bugs being- 

 caught at any point where the brass cover comes in contact with the glass 

 dish (text-fig. 2). Until we wore able to design these covers the bugs were 



Fig. 2. 



Cage designed to prevent the insects from catching the tarsi at the point of contact between 

 the glass dish and the metal top. The spaces marked A and B are large enough to 

 allow the legs to move about freely, but are too small to admit any part of tlie body. 



fretjuently mutilated, for if the tarsus is caught, the entire leg of the bug is 

 sacrificed, for the leg always gives way at the proximal end of the femur. 



Such mutilation apparently does not seriously interfere with the functional 

 activity of the bugs, for in one case a female that had lost three legs 

 continued to mate and lay eggs quite normally. The greatest danger lies in 

 the fact that a bug in this mutilated condition cannot always regain its 

 normal position if it has, by chance, dropped on its back, for in this position 

 even the adult bugs frequently die in a few hours. 



The food chosen for our experiments was wheat and orchard grass while 



