124 THE PERIODICAL CICADA. 
THE LOCATIOX IX THE SOIL. 
There has ])een great diflerence of opmion as to the depth beneath 
the soil reached by the larvse and pupae. In all of the extensive 
excavations which have been made on the Department grounds in 
following the results of the experimental plantings, specimens have 
rarely beenfound at a greater depth than 2 feet below the surface and 
usually between 6 and 12 inches, especially in the first years of the life 
of the insect. This experience is corroborated by the examinations 
made by Professor Riley in ^lissouri, and is fully confirmed by the 
interesting manuscript notes left on this subject by Doctor Smith, 
wliich are here reproduced: 
The deptli in the eartli to which it descends depends upon that of the vegetable 
soil, and its location is at the bottom of the soil, except perhaps in some of the deep 
soils of the West and the alluvial soils, where the depth of its descent is probably 
only sufficient to protect it against the inclemency of the weather. This is generally 
from 12 to 18 inches and sometimes 2 feet. It never changes its locality from the 
time it enters the earth till it emerges. The cells in which they shut themselves up 
are, inside, well finished and smooth, of a sufficient size to accommodate them; but 
outside they are mere lumps of clay and afford by their appearance no clew to their 
internal cliaracter. It is this fact that has caused all the doubt and mystery al)out 
their place of residence and habits during their long continuance in the earth. A 
gentleman in the winter of 1850-51 was excavating on the side of a low hill for the 
purpose of building a wall on West Baltimore street. The excaA^ation was about 150 
yards long and 6 to 18 feet deep to the level of the paved street. This hill had been 
covered in former years with trees and shrubbery, and had been one of the fields of 
obserA^ation in 1834. I watched this excavation daily and found the cells of the 
locusts thrown down in the greatest abundance. The lumps of earth containing 
the cells would roll down the heaps of earth just as others did, affording not the 
slightest indication of their internal contents. But as the pick or the spade of the 
workmen struck a cell in its place in the banks it readily broke open and the Isltxh 
was exposed. AMien the excavation was completed the observ-er standing in the 
street had a fine view of the broken cells in the bank. From one end of the bank 
to the other the cells were plainly visible, appearing like small augur holes, and all in 
a regular stratum of earth about 18 inches below the surface of the earth, from 2 to 4 
or 5 inches apart, and none more than 1 or 2 inches higher or lower than the others. 
The internal size of the cells was from 1^ to 2 inches long and about three-fourths of 
an inch wide, forming an oblong cavity verj,^ smooth in its walls. The particles of 
earth of which the cells were composed had evidently been agglutinated together 
by some viscid fluid secreted by the insect. This is their habitation during the whole 
seventeen years, or until they prepare for their ascent. 
In the face of the testimony given above there are records also by 
apparently trustworth}^ observers which seem to indicate that the 
larvse are capable of going to much greater depths. An instance of 
this sort is reported by Mr. Sadorus, of Port B3Ton, 111., who built a 
house in 1853 and found that they came up in his cellar in 1854. 
Others have reported fuidmg them at a deptli of 10 feet or even more 
l)elow the surface. A rather remarkable instance is recorded b}- Mr. 
Henry C. Suavely, of Lebanon, Pa., in wliich the Cicada pupa^ are 
reported to have worked their way tlirough a hard mass of cinders 
al)()ut 5 feet in thickness, wliich had l)een hnnly compacted. 
