PHRYGANEID&. 
DESCRIPTION OF THE |,ARvA.—The length of the larve is 17 
mm., and the breadth at the third thoracic segment is 2.5 mm. 
PHRYGANEA CINEREA. 
21. Larva. Head and thorax. 23. Larva. Distribution of gills. 
22. Larva. Frons. 
Head.—Figure 21 shows the color pattern of the head. Its 
ground color is straw-yellow, marked as follows: A median mark 
begins on the front margin of the frons and extends back about 
three fourths of its length; a mark begins above the base of each 
mandible and extends diagonally back between the eye and the 
frons to the hind margin of the head; a line begins behind and 
below each eye and extends diagonally upward and backward to 
the hind margin of the head, where it meets the dorsal marks of 
the thorax ; the under side of the head is without marking, except 
for a narrow margin of brown at the base of the mouth parts. The 
eyes are black. 
The Thorax.—The prothorax is straw-yellow with dark marks. 
which form continuations of the lateral marks of the head and 
converge toward the mid-dorsal line as they approach the hind 
margin of the segment; the epimera are dark-brown. 
The meso- and meta-thorax are marked above with two almost 
parallel dark stripes which form continuations of the dark marks 
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