244 Proceedings of Indiana Academy of Science 
measured the aforesaid joints, taking the average length of the joint 
as the ordinate and the number in a brood as the abscissa, and con- 
structed Figure 1. The figure showed that the number in a brood did 
increase with the length of the third joint of the peduncle of the second 
antenna. Therefore, I feel safe in concluding that the number in a 
brood increases with the age of an animal. 
I have not had the good fortune to observe the number of young 
in two successive broods of the same female. However, Sexton and 
Mathews (13) state that in Gammarus chevreuxi, the number of eggs 
seemed to increase with age, e.g., in the case of one individual the 
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ae Seas wd 
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js shessesus: 
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ine 
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" FIGURE re 
Figure 4. Ordinate and abscissa same as in Figures 2 and 3. 
Broods extruded between August 16 and September 26. 
