June 15,1914 
Feeding Habits of the Boll Weevil 
237 
lived for 21 days, the average longevity was 4.4 days. In this series no 
eggs were deposited. 
This species of mallow probably ranks about the same as Callirrhoe 
involucrata as a host plant for the boll weevil. The buds are smaller, and 
consequently the chance of breeding is very slight. Both the buds and 
blooms seem to be of some nutritive value for the boll weevil. 
FEEDING EXPERIMENTS WITH HIBISCUS SYRIACUS 
Hibiscus syriacus L. is a large, woody perennial, commonly called “white 
althea.” Quite a number of the plants were found growing in lawns and 
cemeteries throughout Victoria. Several cultural varieties are found, 
the chief differences being in the color and form of the bloom. The color 
varies from pure white, through pink to blue and purple. The most 
important difference, however, is in the arrangement of the stamens and 
petals. The latter vary from a single row to a great number very 
irregularly arranged. 
The buds are covered with the tough pilose calyx until they begin to 
open. Superficially a section cut thiough a bud shows the interior 
tissues to be much the same as in cotton squares. There is the same 
arrangement of the petals and immature anthers. 
The foliage is very tough, being so different from the tender, succulent 
foliage of cotton that the boll weevil could not be expected to feed upon it. 
Attention was first attracted to Hibiscus syriacus by the fact that on 
June 16 the writer found a boll weevil feeding on the anthers of a bloom 
at Victoria. The plant was a large one in the rear of the laboratory and 
stood about 30 feet from a small patch of cotton which was rather heavily 
infested with boll weevils. When found, the boll weevil was busily eating 
the pollen of the bloom and had destroyed almost all of the anthers. 
Since this was the first record of the species being found feeding on any 
plant except cotton and Thurberia (Arizona wild cotton), it was con¬ 
sidered advisable to make thorough tests of the longevity of the boll 
weevil on H . syriacus , and also to determine whether they would breed 
in the buds. The experiments with this aim may be divided into three 
series, according to the locality from which the boll weevils were derived. 
EXPERIMENTS WITH TEXAS BOEE WEEVIES 
The first series consisted of Texas boll weevils (Anthonomus grandis) 
either collected in the field or reared from cotton squares in the laboratory 
at Victoria. Different lots were tested on buds alone, blooms alone, and 
on buds, blooms, and young fruit together. 
In order to test the exact nutritive value of buds alone, one series of 
10 boll weevils was started on buds alone. The results from this series 
were very surprising. Feeding was noted on only 2 days, and the 
maximum longevity was 5 days, with an average for both sexes of 3.7 
days. This length of life is very little above that for unfed weevils, and 
it is extremely doubtful whether the buds prolonged the life of any of the 
boll weevils in the least. This is quite in accord with the fact that in all 
series offering a choice of food there was very little feeding on the buds. 
Owing to the fact that in the feeding series where a choice of food was 
offered the boll weevil fed so very much more on the blooms than any 
other part of the plant, another experiment was conducted to determine 
the length of life of boll weevils fed only on blooms from the time of their 
emergence. Six insects were used, and they fed every day from the 
