NORTH AMERICAN CADDIS-FLY LARVE. 
Thorax.—The dorsal markings are shown in figure 59. The 
prothorax bears minute forward-pointing spines on its cephalic 
dorsal margin; its sete are long, some equal to the length of the 
segment; a raised, black collar-like ridge extends from the base 
of the legs over the dorsum of the caudal margin of the segment, 
except at the median area, where it is broken; the ventral surface 
is white, except a brown spot which bears two darker marks near 
its caudal margin, and a small darker spot behind each leg; the 
fleshy horn is curved and well developed. The mesothorax is white 
beneath, with four dark spots near the caudal margin. The meta- 
thorax is white on the under side, with two broken dark marks. 
Legs.—Brown, with darker margins, and armed with numer- 
ous long black sete. 
Abdomen.—The humps are well developed; the dorsal hump 
bears a pointed, finger-like process, and the lateral humps are 
rounded; groups of sete occur at the sides of the humps; about 
six large sete and several small ones occur on the ventral surface 
of the first segment ; other segments do not bear large setze on their 
ventral surfaces; segments 2 to 7 bear single small sete on each 
side of the medium line above; segment 8 bears a row of about 
ten sete across its ventral surface ; segment 9 has an oval chitinous 
plate on the dorsum, which bears four large and many small sete ; 
each drag-hook has three small teeth at its base and is preceded by 
a chitinous plate bearing about ten set; a row of three large sete 
occurs inside of each drag-hook and behind the chitinous plate; 
the lateral fringe is black and well developed ; it extends from near 
the cephalic margin of segment 3 to the caudal margin of seg- 
ment 8; above the lateral fringe on each segment occur minute, 
brown, paired spine-like processes; the gills are well developed ; 
their number and distribution are shown diagrammatically in 
figure 60. The weakly chitinized portions of the entire larva are 
thickly set with minute spines. 
DESCRIPTION OF THE Pupa.—Length, 13—17 mm.; breadth, 
4—4.5 mm. In life the color of the thorax and appendages is 
brown, the abdomen is green, and the lateral fringe is deep black. 
The antennz extend back to about the caudal margin of the eighth 
segment; they bear groups of short setz on the dorsal sides of 
the second segments; each side of the labrum bears a group of 
about six long, hooked sete; a row of sharp, curved forward- 
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