Evening star., 1936-05-23
By Thomas r. Henry.


w yITHIN the past week a
M large part of the Eastern
v " area of the United States
has witnessed one nf the
weirdest phenomena in natural his
tory.
Out OF the depths of the earth have
appeared countless billions of red-eyed,
crablike insects They emerged with
out any previous warning, and within
few hours the woodlands were a
bedlam with their wild chorus of nup-
tials and death.
This is the time predicted for the
largest exodus yet known of the
periodical cicadas, popularity known as
the 17-year locusts.
For II years they have lived in dark
chambers from to 4 feet under the
earth. Some strange impulse is about
to strike them all simultaneously and
start them tunneling upward to the
sunlight, mating and destruction.
They will remain above the earth
only long enough to start new gen.
Grafton. This new generation, immedi-
ately upon birth, will burrow into the
ground to wait for another II years
before starting upward to repeat the
weird process.
Nobody knows what mysterious
forces impel this uncanny migration
out of the darkness. Entomologists
know only that it is bound to happen.
1t has recurred with almost clocklike
precision for more than two centuries.
The time can be predicted within a
week.
The periodical cicadas appear sud-
denly during the last week of May in
the Northern States and during the
last week of April or first week of May
In the South. The ground, over limit
ed areas. Is riddled with emergence
holes from which the awkward, cray
fsh-like pupae come forth. Emer-
gence usually takes place in the night.
and in the morning vast numbers of
empty pupal cases are found on the
tree trunks. twigs, leaves and almost
every available support. Shortly after
the pupae come out of the ground the
case splits along the middle of the
back and the adult works its way out.
When it first emerges it is a small,
bizarre looking animal-milky white
with bright red eyes. 1t soon hardens,
however, and assumes a more somber
coloring. The males emerge first.
often several days before the females.
They also disappear first, and late in
the season only females can be found.
After the first Of July the insects be-
come very scarce, and few survive into
the second week of that month.
ONE Of the weirdest features of the
invasion of the cicadas is the song
of the males-they alone have sound
producing apparatus. The song has
no resemblance whatever to the shrill
undulating screech of the annual
locusts, common in August and Sep
tember, and known as the dog day
cicadas." First there is a prolonged
"burring" sound. the individual notes
of which become lost in the continu-
Gus hum Of the millions. Next there
is the so-called pharaoh no<e, charac-
terized by a slightly different burning
sound from that of the chorus. It
usually is sustained only about five
seconds, when it terminates with an
abrupt falling note. Then it Is re-
peated indefinitely, at intervals Of
two to five seconds.
When each note is begun, the singer
lifts his abdomen to q rigid, horizontal
position, evidently thus opening the
ventral drum chambers. The males
utter the pharaoh song as they sit in
the bushes, or on low branches of
trees. The community singing Is
always done at the tops of trees.
The third note is soft, purring
sound Of one syllable. which often is
heard from those sitting low in the
bushes. 1t is shorter than the pharoah
sound and lacks the abrupt, terminal
drop. Finally, when . male appears
to be surprised or frightened he utters