NORTH AMERICAN CADDIS-FLY LARVE. 
pletely dry during the droughts of summer. In the shallow edges 
of the Cove, in Bools’ Backwater, and in most similar situations of 
the region, they are not uncommon dwellers. 
Hasrrs.—Members of the species are bottom-crawlers, where 
their cases, closely resembling stems and grasses, are detected with 
no little difficulty. 
Before pupating the larvae wrap themselves securely, including 
their cases, in folds of the leaves of submerged plants or grasses. 
In this condition they are so perfectly concealed that their de- 
tection requires careful examination of every grass-blade. 
Foop or LArva:.—Raspings from submerged sticks and plants 
form the food of the larve. In the raspings are found diatoms 
and other microscopic organisms, as well as wood and plant frag- 
ments. 
If one watches a larva feeding upon a diatom-covered stick he 
will plainly see a trail of clean wood left behind the slowly moving 
larva. 
DESCRIPTION OF THE Larva:.—Length, 15 mm.; breadth, 2.5 
mm. The chitinous parts are light-brown, with a darker pattern 
of slight contrast, as shown in figure 67. Details of marking are 
subject to some variation in different specimens, but there is 
enough uniformity of pattern to make color characters of value in 
classification. 
Head.—An ill-defined area of brown begins at the base of each 
mandible and extends back, adjacent or close to the margin of the 
frons and above the eye, to the caudal margin of the head; when 
this mark does not touch the frons, the area between it and the 
frons is almost colorless ; each eye is located on the upper cephalic 
side of a light-colored circle ; behind the eye the entire head is more 
or less marked with muscle-attachment spots; in front of this area 
the under surface is uniform brown. The frons (figure 68) is 
brown, with a light mark of varying size extending back from the 
median part of the cephalic margin, and a light-colored area be- 
hind the muscle-attachments spots ; in some specimens the margins 
behind the constrictions are light-colored; the muscle-attachment 
spots are dark, but not strongly contrasting in color. 
Thorax.—The prothorax is light-brown, margined with dark- 
brown or black, and with varying marks of brown (figure 67). 
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