August, 1944 



Ross: Caddis Flies of Illinois 



209 



2-2-4, leg spines as in fig. 69 ; wing vena- 

 tion reduced, front wing, fig. 712, with 

 radial sector only two branched, hind wing 

 narrow with a wide, curved band of black 

 scales extending above cubitus along the 

 basal two-thirds of the wing; seventh ster- 

 nite of abdomen with a mesal, sclerotized 

 process, eighth sternite with a band of hair 

 along apex. 



Male genitalia, fig. 713: tenth tergite 

 divided down meson to form a pair of long, 



Fig. 713. — Beraea gorteba, male genitalia. 

 A, lateral aspect; fi, ventral aspect; C, dorsal 

 aspect. 



pointed, semimembranous lobes; arising near 

 its base are a pair of long, sclerotized, sin- 

 uate rods and a pair of short, ovate cerci; 

 claspers complex, their base fused on meson, 

 apex comprised of ( 1 ) a quadrate ventral 

 plate which is produced into a long, curved 

 basal filament, (2) a stout hook which 

 bears a small cushion of setae on the mesal 



margin near base and (3) a curved, mem- 

 branous dorsal lobe which bears long setae ; 

 aedeagus short, its extreme base vasiform, 

 the apical portion forming a wide, convolut- 

 ed ventral area with a pair of slender scle- 

 rotized styles, a pair of short membranous 

 lobes and a pair of sclerotized dorsal lobes. 



Holotype, male. — Five miles southeast 

 of Roberta, Georgia: May 8, 1939, P. W. 

 Fattig. 



This species is similar in general structure 

 to nigritta, differing in having smaller an- 

 terior warts on the head, only a very short 

 epicranial stem on the head, and the antero- 

 dorsal angle of the head much less produced 

 than in nigritta. Additional material may 

 show these characters to be only antigenetic. 



ODONTOGERIDAE 



The genus Psilotreta is the only repre- 

 sentative of this family in the eastern states. 

 It contains a number of species which are 

 treated on page 285 and following. 



GALAMOGERATIDAE 



The family is represented in the eastern 

 states by two species: Ganonema arneri- 

 canum, a brown to black species with five- 

 segmented maxillary palpi, known from the 

 eastern and northeastern states; and Aniso- 

 centropus pyraloides, an orange-brown spe- 

 cies with six-segmented maxillary palpi, 

 known only from Georgia. The larvae of 

 Ganonema make a case by hollowing out a 

 solid piece of twig (Lloyd \9\5b). 



LEPTOCERIDAE 



All the larvae in this family make cases, 

 using a variety of materials and constructing 

 cases of various shapes. The adults are 

 slender, frequently exceedingly so, and have 

 long, slender antennae. The maxillary palpi 

 are similar and five segmented in both sexes. 



This family is well represented in Illi- 

 nois, and various genera and species occur 

 in a wide variety of streams, ponds and 

 lakes. At times large swarms of Oecetis 

 and Athripsodes occur along large rivers, 

 such as the Ohio and Illinois. Their most 

 conspicuous numbers, however, occur in the 

 glacial lakes of the northeastern part of 

 the state (see p. 10). Here they form the 

 dominant part of the caddis fly fauna. 



Representatives of all seven Nearctic gen- 



