British Species of Caddis-flies. 83 
finger-shaped, straight, dilated towards the apices ; app. intermed. 
long and needle-shaped ; app. inf. with a broad dilated base end- 
ing in two finger-shaped prolongations of equal length; ventral 
surface of the antepenultimate segment with one long central tes- 
taceous spine, and three or four smaller ones on each side; an 
indication of these spines is also to be found oa the penultimate 
segment in the form of small tubercles. In the female there are 
two obtuse hairy superior valves. 
Expanse of fore-wings 6—9 lines, the females the largest. 
Larva: Head, pronotum and mesonotum dark pitchy-brown ; 
three paler spots on the pronotum. Metanotum testaceous, with 
brown markings. Legs pitchy-brown externally. First abdomi- 
nal segment testaceous, the others yellowish, Anal crotchets very 
small, brown. 
Very common in summer and early autumn about small rivers 
and streams. 
The types of picicorne and nigricorne, Pictet, seem to be iden- 
tical, The larvae are described as somewhat different, but this 
may be owing to variation. The figure of that of nigricorne 
accords moderately well with what I take to be the larva of S. 
pallipes. 
B. First apical cell in the anterior wings extending to near the base 
of the discoidal. (PI. V. fig. 3c.) 
2. Silo fumipennis, n. sp. (Pl. XII. figs. 3, 4, app.) 
Antenne, head, palpi and thorax black ; in the female the basal 
joint of antennze, head and prothorax clothed with pale hairs. 
Anterior wings in the male smoky-black, somewhat shining; in 
the female greyish, subhyaline, not thickly clothed with yellowish 
hairs. Posterior wings pale smoky-black, subhyaline, with grey 
cilia ; the fold in the male not conspicuously darker. Legs dark 
reddish-brown; thighs somewhat fuscescent, especially the anterior. 
Abdomen dull blackish, with paler lateral lines, most evident in 
the female. In the male the lobe is very long and pointed, con- 
spicuously testaceous; app. sup. very small and obtuse; app. 
intermed. forming two long, narrow, obtuse blades, placed close 
together, slightly separated at the tips, and acting as an upper 
cover to the penis; app. inf. somewhat pointed, the apex appa- 
rently bifid; ventral surface of the antepenultimate segment with 
one long central spine, and from two to four smaller ones on each 
side. In the female the superior valves are longer and more 
pointed than in the last species. 
G 2 
