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JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 13 
not within 6 inches of the surface. In the east and central part of the 
area, 1 mature larva was collected at the base of a plant, 1 pupa in a 
plant at the surface of the ground, and 2 in plants at points about 4 
inches above the surface. From 1 of the last 2, 1 male C. pertinax was 
reared. 
In the western part of the swamp, 3 larvse, 3 pupae and 1 male and 3 
female C. pertinax adults were taken, in conditions as follows: 1 
larva in base of a cat-tail plant 4 inches below the surface of the soil, 
which subsequently produced a female C. pertinax adult; 1 larva in 
base of plant 2 inches below the surface, which afterward produced 
an adult male C. pertinax; 1 larva in base of plant 3 inches below the 
surface, which died; 2 pupae in soil 2 inches below the surface, which 
subsequently produced 2 adult female C. pertinax; 1 pupa (position 
not noted), which was crushed; 1 adult male C. pertinax, in cell, prob¬ 
ably the pupa cell, in soil, 1 inch deep; and 3 adult female C. pertinax 
on the surface of the soil, among cat-tails. 
This series shows a definite tendency to pupation in the stems, the 
trait appearing in 3 instances recorded above, with soil pupation in 
like number of instances, as observed September 16, 1919. 
Viewed in their relation to water or excessively wet soil, there were 
the 3 examples of stem pupation and 1 of soil pupation, in the 3 pupae 
and 1 prepupa taken at the east and central portion of the swamp 
where the stream and the water level were about at the surface of the 
soil. This provides a 75 per cent example of stem pupation where too 
much water prevails at the base of the plants, but no tendency was 
observed in this direction among the specimens taken where the soil 
was several inches above the water horizon. On July 29, at the west¬ 
ern end, where the soil was firm, only 1 specimen was taken in so 
advanced a stage as a pupa, and this was in the soil, outside of its host 
plant. 
The Economic Aspects 
From the economic standpoint, the preceding notes show that the 
common cat-tail, a widely distributed swamp plant, is subject to 
liberal infestations by Calendra pertinax, an insect which, under favor¬ 
able conditions, may prove very destructive to corn. These notes are 
based on 12 cat-tail areas represented by 9 post office centers, in 3 
states. The writer has only one other record of cat-tail area exam¬ 
ined, at Mt. Pocono, Pennsylvania, where a brief examination was 
limited to a small clump of plants rather remote from the open water. 
No evidence of C. pertinax work was found, but this negative record 
is not dependable. It is anticipated that all cat-tail beds are more or 
less infested with C. pertinax, and to be regarded accordingly as a 
menace to corn in every case where cat-tail sod is broken for corn. 
