A SUCCESSFUL SEVENTEEN-YEAR BREEDING RECORD. 115 
was found to be thickly filled with larvee, so much so that a single 
spadeful of earth would often turn up half a dozen or more. In the 
spring of 1897 the larve had reached the fourth stage and were still 
very abundant in the soil. Examinations were made from time to 
time showing these larve to be still present in the soil about the trees 
where the eggs had been distributed, going through the slow process 
of growth and transformation which has been described elsewhere. 
That a successful outcome was sure to be had in this experiment was 
demonstrated in the early spring of 1906, the year for the appearance 
of this brood, the ground about the planted trees exhibiting many of 
the exit holes of the insects which are made to the surface long before 
the insect emerges. These holes under certain trees were so numerous 
as to indicate the emergence of thousands of cicadas. Under one tree 
a count and estimate were made of more than five thousand openings, 
and under other trees the openings ranged from a few hundred to from 
one to three thousand. The actual emergence took place between 
May 14 and 21. The writer visited the grove on two evenings and 
witnessed the issuance of numbers of cicadas and collected some 
specimens. In spite, however, of the considerable number of cicadas 
which actually emerged, none was seen on the trees during the days 
and weeks following emergence. Each morning about the planted 
trees would be found a considerable group of blackbirds (Quiscalus 
quiscula), which evidently had been feasting on the newly-issued 
cicadas. The cast pupal shells were numerous on the trunks of the 
trees and especially on the foliage, and also on the ground, but scarcely 
a single Cicada escaped the sharp eyes of these birds, and the charac- 
teristic song was not heard during June in this grove, although thou- 
sands of adults had come forth. 
At none of the examinations were Cicadas found of this brood under 
any of the trees except where eggs had been distributed, and no 
emergence holes appeared under other trees. The record from the 
planting to the emergence of this insect is therefore complete, and 
gives the demonstration by actual transfer and breeding record of the 
long period of the 17-year brood, a demonstration which, as indicated 
at the outset, was-entirely unnecessary to show the correctness of this 
extraordinary hypogeal term. 
The absolute failure of these insects to establish themselves when 
planted in such enormous numbers, and even when the underground 
period had been successfully passed, owing to the relentless onslaught 
of birds, is a striking illustration of what is happening every year 
with the different broods in nature, especially in thinly forested 
regions, and accounts for their great reduction in numbers and the 
practical disappearance of many local swarms formerly abundant. 
It also shows that there may be emergences in considerable numbers 
