THE BED SPIDER ON" COTTON". 



21 



Carolina. Considering the fact that North Carolina, Georgia, Ala- 

 bama, and Mississippi are known to suffer from the pest practically 

 to the same degree as does South Carolma, it is within all probability 

 that the Southeast, during a severe red-spider year, may suffer a loss 

 of 82.000,000 from the ravages of this pest. As discussed under 

 another heading, the occurrence of the pest during certain years is 

 comparatively light, and the resulting injury is correspondingly 

 reduced. 



Fro. r,. — Diagram illustrating the sequence of the usual 17 generations of the red spider in the course of 



one year. (Original.) 



GENERATIONS OF THE RED SPIDER. 



Regarding the number of generations at any given locality very 

 little ha.s been published. Ewing (1914) states that in Oregon the 

 activities usually begin early in May and that hibernation com- 

 incjices in October. This furnishes an active season of about 180 

 days, which, divided by 19.7 days (tlu; duration of tlie life cycle 

 biused on his uverugesj, gives nine generations occurring at Corvallis 

 for the season. Worsham (\U\(\) slates that in Georgia there are 10 



