LIMNOPHILID&. 
Legs——Brown, with darker markings along the edges and 
around the sete. 
Abdomen.—The first segment above has several circular brown 
spots surrounding sete, a glabrous area borders the caudal margin 
of each lateral hump, and a group of four or five fine sete is 
present above and below each lateral hump; on the ventral side 
there are a few scattering sete and a bilobed median mark, con- 
taining four or five sete in each lobe; the entire surface of the 
first segment is thickly set with very minute spines. The lateral 
fringe of black hair begins near the posterior margin of the 
second segment and extends to the posterior margin of the eighth 
segment. The arrangement of gills is diagrammatically shown in 
figure 82. A slight variation of gills occurs on the caudal seg- 
ments of different individuals. 
DESCRIPTION OF THE Pupa.—Length, 30 mm.; breadth, 6 mm. 
The labrum is longer than broad, extending shelf-like over the 
mandibles and bearing a group of five long, dark-colored, hooked 
sete on each side; two similar sete, but not hooked occur on each 
side near the base, a shorter seta of lighter color points forward 
from the cephalic margin of each lobe and a similar seta occurs 
laterad from each pair of long basal sete; the mandibles are 
straight, without teeth and sharply pointed, reaching not quite to 
the extreme of the labrum; each bears two sete near its base; the 
dorsal part of the first abdominal segment is marked with small 
cross-folds, which give it a striate appearance, and is bordered 
behind with wing-shaped marks, somewhat striate and bearing 
numerous small thorns on their caudal margin, figure 83 ; the lateral 
fringe is black, commencing near the caudal margin of the fifth 
abdominal segment and forming a loop beneath the caudal margin 
of the eighth segment. The antennz reach to the caudal margin 
of the sixth segment. The chitinous plates are shown in figure 83, 
but the number and arrangement of teeth is subject to variation in 
different individuals. 
DESCRIPTION OF THE CAsE.—The larval cases, figure 87, the 
largest and most bulky in our streams, are constructed of frag- 
ments of twigs and bark, which vary greatly in size and shape. 
These fragments, arranged with little regard for system or sym- 
metry, are fastened securely together by means of silk, and the 
59 
