
AQUATIC INSECTS OF FRESHWATER 

, 
stones in the streams and feed on the larve and nymphe of May-flies, 
Stone-flies and other aquatic insects. The larval stage lasts three months 
and longer, but the pupal stage is quickly passed, and in less than a month 
after the larva leaves the water to make a cell for itself nearby, in which 
to undergo the metamorphosis, the adult insect or imago appears. 
Some of the 
common species 
of Sialiade, of 
smaller size, the 
Alder-flies, or 
Chauliodes, are 
C. pecticornis, hav- 
ing greyish wings 
and featherlike 
antenna, and: C. 
serricornis of a 
brownish - black 
color with white- 
spotted wings. 
Four other species 
are not quite so 
generally distrib- 
uted. — Ally ehe 
Dobson larve are 
carnivorous and 
destructive to 
small fishes and 

snails. 
May-F igs or 
15 SHAD-F igs _ be- 
SG. once . long to family of 
1. May-fly, Heptagenia pulchella, of the family Ephemeridz. Ephemeride, sig- 
2and';3). 88 Batis pygmea, lateral and dorsal views. PER ‘ 
4. Stone-fly, Leuctra tenella, of the family Plecoptera. nifying lasting but 
5. Caddice-fly, Phryganea interrupta, of the family Hydropsychide. z h h 
Enlarged x 6. aday. They have 
6. ss Phryganea interrupta, Imagos at rest. Natural size. : 7 
fe Ch larva, Enlarged x 5. delicate aes m 
8. =e pupal case. Enlarged x 4. ; branous wings, 
g. Black-fly, Roederiodes juncta, of the family Empidide. Enlarged x 10. ; 
10. ow larva. Enlarged x 5. with a fine net- 
ils ce upa. ee xc S ° 
Cee ae oy ae ea Enlarged x 5. ; work of veins, the 
13. Buffalo-fly, Simulium venustus, of the family Simuliide. Enlarged x 5. ae 
g hap of pine: fore wings larger 
14. oe larva. Enlarged x 6. than the second 
TiGe Ce Natural size. 
pair, which latter 
