LEAFHOPPERS OF THE SUGAR BEET. 39 
Cages Jf, and 6 (glass globes upon beets about 8 inches in diam- 
eter). — On July 10. 16 adult leafhoppers. 12 of which were female-, 
were introduced into cage 4. Previous dissections had shown that all 
females were bearing eggs, and the presence of a very few small 
nymphs in the field proved that the earliest ones began depositing 
eggs some time before. It was therefore expected that some of the 
females introduced would begin depositing at once. 
On July 23 these cages were examined, and in the one containing 
the leafhoppers the stems were found to be fairly covered with egg 
scars. Two of the stems were removed and preserved, and found to 
contain 161 eggs — not more than one-sixth of the total number pres- 
ent. A number of females were seen in the cage, but no nymphs. 
July 27 the stems showed still more egg scars, and there was quite 
a number of small nymphs that had apparently been out several 
days. The insects had been in the cage only seventeen days, so these 
eggs must have hatched within thirteen to fifteen days from the time 
of laying, under the conditions found in the cage. Another stem 
was removed and preserved, and the rest left as before. 
On August 3 another stem was removed. The eggs had almost 
all hatched by this time. Some had dried up and a few were found 
just ready to hatch. A few were sticking out of the stalk and looked 
quite fresh, but were probably infertile. Some of the leaves had 
wilted and died, and the remainder were literally alive with small 
to half-grown nymphs, together with a few adults, no doubt the 
remaining parents. 
These ha If -grown nymphs were no doubt those hatched between 
July 23 and 27. and would thus be between eight and eleven days 
old, roughly indicating a nymphal period of between sixteen and 
twenty-two days under these conditions. 
On August 14 this cage was visited again, and the beet found dead 
and dry. From appearances it had been dead several days. The 
few leafhoppers that survived were adults and large nymphs. They 
were so few in number that it was impossible to tell whether they 
were the surviving parents or a new generation, so they were released. 
Cages 6 and 7 (silk scrim 2 feet square). — On July 23, IS nymphs 
varying between one-third and two-thirds grown were introduced 
into cage 6. These were intended to represent the larger ones found 
in the field at that date. 
On July 27 no adults could be seen. 
On August 3 most of the nymphs had changed to adults. This 
period of eleven days was, then, more than one-third and slightly 
Less than two-thirds of the nymphal period. This gives about the 
same result a- the tesl in cage 4. 
Cages 8 and 9 (silk scrim with glass top).— On August :>. 1<» leaf- 
hoppers were introduced into cage 8; of these 23 were females, 
55968°— Bull. G<>— 10 1 
