SEVENTEEN-YEAR LOCUST — SNODGRASS. 399 
a number of times. Finally the ovipositor was sunk so deep that 
the abdomen came up close against the bark and egg-laying began, 
as indicated by the regular contractions of the plates of the ninth 
abdominal segment that operate the ovipositor blades. At short in- 
tervals the instrument was drawn out nearly to the tip and then 
thrust in again, but each time not so deep as the time before. This 
stage lasted another 5 minutes, 15 minutes in all having elapsed 
since the start. Now the abdominal pulsations ceased and the ovi- 
positor was again sunk full length into the wood ; repeated probings 
occupied the next 7 minutes. This was followed by a second period 
of egg laying, lasting 3 minutes, while the thrusts became shorter 
and shorter. Finally, the ovipositor was withdrawn, snapped back 
into its sheath, and the female flew away. The whole operation had 
taken 25 minutes. 
In a number of other cases the females were frightened away at 
different stages of their work, and an examination of these unfin- 
ished nests showed that each chamber is filled with eggs as soon as 
it is excavated; that is, the insect completes one chamber first and 
fills it with eggs, then the other chamber is dug out and in turn 
receives its quota of eggs, when the whole job is done. The female 
then moves forward a few steps and begins work on another nest, 
which is completed in the same fashion. Some series consist of 
only 3 or 4 nests, while others contain as many as 20 and a few even 
more, but perhaps 8 to 12 are the usual numbers. When the female 
has finished what she deems sufficient on one twig she flies away 
and is said to make further layings elsewhere, till she has disposed 
of her 400 to 600 eggs, but the writer made no observations covering 
this point. Probably the cicada feels it safer not to intrust all her 
eggs to one tree, on the principle of not putting all your money in 
the same bank. 
DEATH. 
From the time that egg laying was at its height, about the 10th of 
June, the din of the singing in the woods began to diminish. Many 
insects were from the first killed or mutilated by birds or small 
mammals ; now the ground became strewn with dead bodies or with 
insects still living, but hopelessly injured and dismembered. By the 
13th and 14th of the month the colony was reduced to a very mis- 
erable condition. Great numbers were dead or dying, and a large 
percentage of the living were walking around on the ground in 
various stages of disfigurement. Wings were torn off; abdomens 
were broken open or gone entirely; mere fragments crawled about, 
still alive if the head and thorax were intact. It was almost a 
gruesome sight to see these half creatures, the males often with the 
great muscle columns of the tympana exposed and visibly quivering. 
