LIBRARY

368 COLLEGE ENTOMOLOGY
part small, brown or black in color, and rather feeble fliers, but some species
are quite agile in their somewhat erratic movements over the surface of the
water at dusk. The dominant genus, Sialis Latr. is Holarctic and two other
larva of Sialid
(al'.r N .. dhom)
FIG. 128. The California alderfly. Sialis ca/ijornicus Banks. and mouth parts and antennae.
The larva. pupa. and eggs are of other species.
genera, Austrosialis Tillyard and Stenosialis Tillyard, are Australian and
Tasmanian.
The luteous alderfly, Sl'alis flavilatera Linn. (lutaria Fab.), of northern
Europe is brownish-black with yellowish-brown wings. It is a weak and clumsy