Ts THE PERIODICAL CICADA. 
ticularly the variation in the structure of the peculiar comb-like 
organ which is found on the apical margin of the front femora, together 
with the important differences in the hairy covering of the body and 
legs. 
TECHNICAL DESCRIPTION OF THE DIFFERENT STAGES. 
First larval stage-—The newly hatched larva (fig. 47, a) is about 1.8 
mm. long from tip of head to the extremity of the abdomen, is rather 
slender and of a nearly uniform thickness throughout, presenting, 
however, the general characteristics of the later larval stages. The 
body is clothed with numerous 
scattering long hairs. The gen- 
eral color is creamy white, with 
h prominent, deep red, almost black, 
eye spots. The antenne, beak, 
and legs are, relatively with other 
stages, very large in comparison 
with the size of the body. The 
anterior legs are developed in 
general as in the later stages, 
though lacking the femoral 
comb-like organ which begins in 
the second stage and the minute 
second subapical tooth on the tibia 
which appears in the fourth stage. 
The anterior tibize are also 
more slender and the mandible- 
like tip is more sharply pointed. 
The row of stiff hairs for retain- 
ing the earth excavated in bur- 
Fie. 47.—First larval stage: a, newly hatched TOW EEg [OUI in the 
larva; b, antenna of same; c, larva eighteen later stages, 1s but sparsely rep- 
months old; d, enlarged anterior leg of same. pegented. The anterior tarsus 
(Author’s illustration.) : je 5 : 5 
is inserted considerably within 
the tip of the tibia, projecting beyond the Jatter, and is armed 
at its extremity with two nearly equal, curved claws, similar to 
those on the middle and hind tarsi. The basal joint of the two- 
jointed tarsi in all the feet is very minute and with difficulty detected, 
and in fact becomes still more inconspicuous in later larval develop- 
ment. The antenne are seven-jointed, as in all the subsequent larval 
and pupal stages (one of the characters distinguishing this species 
from other allied species, particularly C. tibicen, which has an addi- 
tional joint); but the presence of a very prominent antennal tubercle 
gives an appearance of eight joints, the number which I have hitherto 
assigned to it. The first true joint is robust and a little shorter than 
