LIBRARY

MEGALOPTERA 371
and trout. They are formidable-looking creatures that occur under stones in
slow or swift water and are predacious on the naiads of dragonflies, stonefiies,
mayflies, and other aquatic forms. Two or three years are required to complete
the larval siage, and pupation occurs in a cell constructed under stones, logs,
or refuse on the banks out of the water. The eggs are laid in masses of several
thousands on branches, rocks, and objects over the water. Adults appear in
early summer.
The dobson, Corydalus cornutus (Linn.) (Corydalis), is probably the most
interesting species because of the greatly elongated and horn-like mandibles
of the males which are nearly half the length of the body. The length of the
adults may vary from 100-130 mm. The species occurs in eastern North
America. Its western counterpart, belonging to a separate subfamily, is the'
smaller California dobson, Neolzermes callfornicus (Walker), which is but
43 mm. long. The New Zealand Arclzichaztliodes dubitatus (Walker) varies
from 50-100 mm. in length. The larvre are called toe-biters.
The genera Chlorina Banks, Corydalus Latr., Platyneuromus Weele, Chauliodes
Latr., Nigronia Banks, Neohermes Banks, and Protochauliodes Weele are
American; Acanthacorydalis Weele, Hermes Gray, Neohermes Weele, Neuromus
Rambur, Ctenochauliodes Weele, Neochauliodes Weele, and Parachauliodes
Weele are Asiatic; Archichauliodes Weele is New Zealand; and Cltloroniella
E. Petersen, Platychauliodes E. Petersen, and Tceniochauliodes E. Petersen are
African.
SELECTED REFERENCES
DAVIS, K. C., "Sialididre of North and South America," N. Y. St. Mus. Bull., 68, Ent.
18, pt. 7: 442-486, figs. 20-26, pIs. 51-52, 1903.
KARNY, H. B., Biologie der Wasserinsekten, pp. 1-3U, 160 figs., bibliography, Wagner,
Wien, 1934.
LATREILLE, P. A., Histoire natztrelle generale et particuliere des Crzestaces et des Insectes,
III: 289, Dufart, Paris, 1802.
PETERSEN, EBSEN, "Megaloptera. fam. Raphididre," Gen. Insectorum 154: 1-13, 2 pIs.,
1913.
Ross, R. R., "Nearctic alder flies of the genus Sialis (Megaloptera, Sialidre)," Bull.
Nat. Hist. Surv. Ill. 21: 57-78, figs. 1-63, bibliography, 1937.
STITZ, B., "Megaloptera," Bioi. Tiere Deutschlands. lief. 22, t. 35: 35.29-35.47, 36 figs.,
16 refs., 1926.
--, "Megaloptera," Tierwelt Mitteleuropas, 6 (1) lief. 1: xiii-xiv + 1-3, 4 figs., 1928.
TILLYARD, R. J" "Australian Megaloptera or Alder-flies," Proc. Linn. Soc. N. S. W.
XLIII: 819-825, 3 figs., 1918.
--, The Insects of Australia and New Zealand, pp. xi + 560, 44 pIs., figs., Angus &
Robertson, Sydney, 1926.
WEBER, H., Lehrbzech der Entomoiogie, pp. XII + 726, 555 figs., Fischer, Jena, 1933.
WEELE, H. W., "Megaloptera," Call. Zool. Selys Longchamps, Brussels, fasc. 6, no. 115:
1-93, 70 figs., 4 pIs., 1910.