PLECOPTERA NYMPHS OF NORTH AMERICA 99 
many short hairs. Mandibles asymmetrical, four unequal, rather 
blunt teeth, followed by a well-developed molar which on the 
dorsal surface is fringed by wide blunt hairs resembling a comb; 
beyond this comb, a small group of long hairs. Maxillae: lacinia 
terminating in two ineurved teeth followed by a fringe of stout 
hairs; galea cylindrical, extending somewhat beyond the lacinia, 
and bearing at the apex a group of small papillae and a few setae. 
Maxillary palpus nearly twice as long as galea, stout, the fifth 
segment with a small cup at the apex in which may be noted 
small papillae. Labium with submentum very large and almost as 
long as wide; mentum very narrow; glossae and paraglossae 
small; the glossae only about half as wide as paraglossae and not 
extending beyond the paraglossae. Both glossae and paraglossae 
eovered at the tip with small papillae, but only the paraglossae 
with long hairs; labial palpus stout and reaching far beyond the 
tip of the paraglossae; third segment ending in a cup-shaped 
depression. Hypopharynx large, rounded in front, and normally 
extending far beyond the tips of the paraglossae. 
Ithaca, N.Y. 
Leuctra decepta Claassen 
(Plate 28, fig. 208.) 
Length of body up to 8 mm.; antennae up to 4 (?) mm.; cerci 
up to 3.5 (?) mm. . 
General color brown with the appendages a little lighter. Head 
wider than pronotum; hind ocelli more than twice as close to 
the eyes as to each other; antennae composed of about forty-five 
segments. 
Pronotum a little wider than long; sides nearly straight or 
slightly convex; angles rather narrowly rounded; surface quite 
smooth, covered with hairs, and with longer hairs on the outer 
margin, especially noticeable at the angles. Cerci with about 
twenty segments. In fully mature nymphs, the genital structures 
of the developing adult may be observed. In the male there oc- 
curs a small tubercle just beyond and below the tenth tergite. 
Within this tubercle may be seen the developing supra-anal 
processes. | 
No nymphal structures have been found by which this species 
ean definitely be separated from other species, and identification 
is possible only through rearing records or by careful study of 
the genital structures in mature nymphs. 
Ithaca, N.Y. 
