February, ’18] 
WEBSTER: STRAWBERRY LEAF-ROLLER 
45 
Variation in Color of Lary^j 
Riley (1869) mentions a variation in color of larvae from light yellow¬ 
ish brown to dark olive green or brown. Other writers have also 
mentioned this variation. This color appears to be seasonal in its 
occurrence, according to our observations in Iowa. During the greater 
part of the season the normal color is a yellow-brown. In September 
and October, as the cooler weather comes on, the larvae assume a dull 
olivaceous color. In the fall both light and dark colored larvae have 
been found at the same time. In spring the overwintering larvae are 
dark in color, but the first generation from eggs are light. 
Length of Pupa Stage 
The pupa stage in summer is much shorter than in spring. From 
meagre data the length of this stage in April and May was found to 
be from 14 to 18 days. In the summer months an average of 6.4 days 
was spent as pupae. This average is from 96 individual records in the 
years of 1914, 1915 and 1916. 
Much difference in the time required was found in different years. 
Much longer time was required during the exceptionally cool summer 
of 1915, than in 1914 or 1916, when it was very hot. The length of the 
pupal stage was essentially the same for both sexes. 
Length of Life of the Moths 
Some data on the length of life of adult moths were secured in insect¬ 
ary cages, where individual pairs were confined for egg records. As a 
rule a little water sweetened with sugar was placed in these cages for 
food. In 1916 honey was substituted for sugar. 
Twenty-four female moths lived on an average of 10.2 days, with a 
range of from 3 to 28 days. Nineteen male moths lived on an average 
of 10.1 days, with a range of from 3 to 23 days. It was thought that 
the males died more quickly in the cages than the females, but the 
average is too slight to consider of any importance. 
In compiling these data only accurate records were used. In some 
cases moths were noted in the insectary experiments as having escaped. 
None of these records are used here, since the time of death of the 
insect was uncertain. 
Bibliography 
The following articles are referred to in this paper. 
1869. Riley, C. V. First Missouri Report, p. 142. 
1884. Forbes, S. A. Thirteenth Illinois Report, p. 87. 
1890. G arm an, H. Kentucky Agr. Exp. Station, Bui. 31, p. 13. 
1901. Stedman, J. M. Missouri Agr. Exp. Station, Bui. 54. 
1908. Swenk, M. H. Nebraska State Entomologist, Cir. 7. 
1909. Smith, J. B. New Jersey Agr. Exp. Station, Bui. 225, p. 17. 
1911. Hart, C. A. 26th Report State Entomologist, Illinois, p. 86. 
