FIG. 167. Periodical cicada 



<?, adult; />, young nymph (enlarged); r, cast skin of full-grown nymph; d, side view of 

 female to show beak, c, and ovipositor, /. (Natural size except b.) (After Marlatt and Riley, 



United States Department of Agriculture) 



FIG. 1 68. Buffalo tree-hopper and twig of apple tree showing eggs and adult 



Adult (enlarged) at left ; a, adult (natural size) ; b, recent egg punctures ; c, bark reversed 



with eggs in position; d, single row of eggs (enlarged); <?, wounds of two or three years' 



standing on older limbs. (After Marlatt, United States Department of Agriculture) 



123 



