Oct. io, 1913 
Serpentine Leaf-Miner 
75 
Luginbill. Mines were also found in leaves of cabbage on May 9. They 
were first noticed in the leaves of rape on July 12, about the time the 
mines were noticed in this plant by Mr. Phillips three years before. A 
series of experiments was carried on from May until November with 
cabbage and rape as host plants, and a maximum of six generations was 
found to occur in that latitude. 
Here again, as is the case wherever these mines are found, a very large 
percentage of the larvae in them were found to be parasitized, and a large 
number of parasites were reared. Oviposition was observed, both in the 
field and in confinement, to take place precisely as in the leaves of alfalfa. 
The mines usually start from near the edge of the leaf, where the eggs are 
deposited, and extend part way around the leaf on the upper side, being 
visible only from above. 
The extent of the damage to the crop under observation was not severe 
and, perhaps, could be reduced by destroying all the old plants at the end 
of the season and plowing deeply in the autumn to bury the hibernating 
pupae. 
Moreover, since cabbage seems to be a favorite food plant during the 
spring, it is readily seen that this crop should not be succeeded by or 
planted near rape, where trouble from this leaf-miner is anticipated. 
MINING IN nBAVES OF COTTON 
While primarily an enemy of forage crops, this miner has been found 
feeding in leaves of cotton in the Southern States. In 1906, adults were 
collected in cotton fields at Cotulla, Tex., by the late Mr. F. C. Pratt, and 
a year later taken in a cotton field by Mr. E. S. Tucker, of the Section of 
Southern Field-Crop Insect Investigations, Bureau of Entomology. Dur¬ 
ing the summer of 1912, adults determined as this species were reared 
from cotton leaves at Batesburg, S. C., and Dallas, Tex., by Mr. E. A. 
McGregor, of the Section of Southern Field-Crop Insect Investigations, 
and by Mr. A. Rutherford. 
The mines were observed at Batesburg by Mr. McGregor from the time 
of the first appearance of the cotton seedlings until July. Table I, pre¬ 
pared by him, shows the percentage of infestation which existed on July 
12, 1912. 
Table I .—Infestation of cotton by the serpentine leaf-miner at Batesburg , C., July 12, 
IQ 12 . 
Plants in row. 
Plants in¬ 
fested. 
Percentage of 
infestation. 
81 
69 
85 
107 
84 
79 
I 5 6 
136 
87 
1 344 
1 289 
00 
1 Total. 
2 Average. 
