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[Vol. 87 
the hunting site for 90 minutes. At the end of this time its size was 
substantially reduced (Fig. 14—an estimated 40% loss of volume) and 
it was no longer sticky. The spiders’ ingestion of balls after about 30 
minute intervals thus probably served to insure that the ball is 
sufficiently sticky. This agrees with Hutchinson’s observations of the 
balls of M. cornigera. The reduction in size contrasts with the almost 
complete lack of shrinkage of the balls of adhesive on the sticky 
spirals of the orbs of araneids such as Metazygia sp., Leucauge sp., 
Fig. 14. Shrinkage of a sticky ball due to evaporation: A. a freshly made ball; B. the 
same ball 90 minutes later. 
