THE HUTS, OK CONES. 67 
owing to the shallowness of the soil, determined either by the nearness 
of the underlying rocks or of a subsoil of a character preventing the 
insects working in it effectively, had responded more quickly to the heat 
of spring and early summer, and the pupae coming prematurely to the 
surface closed and extended their burrows as a means of protection 
while awaiting maturity. The extension of the gallery above the 
ground, though not suggested by Mr. Lander, may be explained by 
the same instinct which impels the insects to burrow upward from its 
subterranean cell. 
In substantiation of his theory, Mr. Lander calls attention to the 
weather records for March and April, 1894, which indicate an unusually 
high temperature throughout the region of the domed burrows, causing 
wild plants to bloom a month before their ordinary season. The occur- 
rence of these structures over burnt areas, which would be acted upon 
more quickly by the sun, supports his belief. Additional support of 
the same kind is an instance recorded by Prof. J. B. Smith 1 in a letter 
received from Mr. J. H. Willets, of Port Elizabeth, X. J. The latter 
states that "On April 24 a fire from the South Jersey Railroad burned 
over several hundred acres of woodland, leaving the earth bare. Six 
days after these fresh holes and raised tubes appeared, and yesterday 
the whole surface was literally covered with them." In further descrip- 
tion he says: 
Imagine yourself standing out in the woods in south Jersey on 100 acres of recently 
burned ground with millions and millions of raised tubes of new earth (clay ground) 
raised above the surface from 2 to 4 inches and from li to 2 inches in diameter, 
sealed at the top, with a hole inside extending down in the earth 12 inches at least, 
and you will see mentally what I saw yesterday physically. 
In this instance also, on the authority of Mr. Lander, the turrets 
ended abruptly at the edge of the burned area. The other instances 
of these structures cited by Mr. Lander also bear out his theory. As 
a rule, they were located on rocky cliffs with uniformly shallow soil or 
in other situations where the soil in which the Cicada could work was 
shallow. In the midst of one of the largest colonies a deep gully 
occurred, 300 or 400 feet wide, in which the soil was a deep loam. Here 
there were no domed burrows, although the hills on either side were 
covered with them, and yet at the proper season the Cicadas appeared 
in the ordinary way in this gully in almost incredible numbers, leaving 
their customary small holes of exit even with the sin lace. 
The occurrence of these cones as described by Professor Newbury, at 
Rahway, N. J., is also confirmatory of this theory, a shallow covering 
of soil over the pupa of a lew inches only being left by the slight exca- 
vation made. 
Dr. E.G.Love, who also studied the problem of the Cicada huts 
very carefully, agrees in the main with Mr. Lander, but differs some- 
what in his explanation. As to the conditions of their occurrence, he 
Annual Report lor 1894. 
