

PLATE 29. A. Male (upper figure) and female (lower figure) of seventeen-year cicada (Cicada 

 septendecim) , often inaccurately called "seventeen-year locust." x. Stridulating organ of the male. 

 It is absent in the female. B. Males and female (middle figure above) of staghorn beetle (Lucanus 

 dam a) . These figures illustrate not only the difference between the sexes, but also the variation in 

 size among the males. 



