August, 1944 



Ross: Caddis Flies of Illinois 



231 



sions, the attachments fairly long, mem- 

 hranous except for a pair of plates which 

 do not touch the bursa. 



Allotype, female. — Brevort, Michigan: 

 Aug. 8, 1936, C. Sabrosky. 



Illinois records are confined entirely to 

 the shore of Lake Michigan. The type of 

 Hagen's variegatus was collected at Chi- 

 cago, the types of aspinosus are from Lake 

 Forest, and we have taken additional speci- 

 mens at Waukegan. The larva, which is 

 unknown, probably lives in Lake Michigan. 



The range of the species extends through- 

 out the Northeast, with a single isolated 

 record from the Kiamichi Mountains in 

 Oklahoma. Records include Illinois, Michi- 

 gan, Minnesota, New York, Ohio, Okla- 

 homa, Ontario, Quebec, Saskatchewan and 

 Wisconsin. 



Illinois Records. — Chicago: June 11- 

 Aug. 27, W. J. Gerhard, 1$, 3$, fm. 

 Waukegan: July 7, 1937, at light, Frison 

 & Ross, 3 9 . 



Athripsodes angustus (Banks) 



I.eptocerus angustus Banks (1914, p. 263); 



c^. 



Larva. — Unknown. 



Adults. — Length 13 mm. Color brown 

 with scarcely any markings. Male genitalia, 

 fig. 784, very similar to resurgens, differing 

 in the longer apical segment of the clasper, 

 more uniform tenth tergite, and the long, 

 fusiform spine on the inner lobe of the 

 clasper. Female genitalia, fig. 801, similar 

 in general structure to resurgens but with 

 supports of the bursa sclerotized for almost 

 their entire length. 



Allotype, female. — Lake Erie, Put-in- 

 Bay, Ohio: Aug. 16, 1937, C. O. Mohr. 



We have only a few scattered records of 

 this species from the northern half of Illi- 

 nois. Little is known about its habitat pref- 

 erence, and the larva is unknown. 



The range of the species occupies a large 

 portion of the Northeast, with a south- 

 westward extension into the Kiamichi 

 Mountains of Oklahoma. Records are avail- 

 able from Illinois, Maine, Michigan, Min- 

 nesota, New York, Ohio, Oklahoma, On- 

 tario, Pennsylvania, Quebec and Wisconsin. 



Illinois Records. — Danville, Middle 

 Fork River: Aug. 27, 1936, Ross & Burks, 

 3 5 . Three miles east of Momence: June 

 22, 1938, Ross & Burks, \ $, . Oregon: 



July 18, 1927, at light, T. H. Frison & R. 

 D. Glasgow, 2$. Richmond: June 20, 

 1938, Burks & Boesel, U . 



Athripsodes dilutus (Hagen) 

 Leptocerus dilutus Hagen (1861, p. 277); d^. 



Larva. — Length 6 mm. Head, pronotum 

 and legs cream color to yellowish, the head 

 with scattered, indistinct, brownish spots on 

 upper portion. Parafrontal areas only about 

 half width of frons. Mesonotum with only 

 a few pairs of scattered hairs, the sclero- 

 tized bars narrow and not sharply angled. 

 Ninth segment with only one or two very 

 short and slender dorsal hairs. 



Case. — Length 7 mm., horn shaped, near- 

 ly round in cross section, constructed of 

 sand grains cemented together to form a 

 fairly smooth exterior. 



Adults. — Length 6-7 mm. Color dark 

 brown, the wings with a few patches of 

 light hair. Male genitalia, fig. 782: cerci 

 short, almost completely fused at base with 

 genital capsule; tenth tergite fairly long, 

 divided at apex into a pair of short, rounded 

 lobes; claspers with basal segment very long, 

 produced into a short ventral projection, 

 apical segment short and somewhat elliptic; 

 mesal process short, narrow at base and 

 widened into a spatulate apex ; aedeagus 

 with two long, black internal spines situated 

 one beyond the other. Female genitalia, 

 fig. 796, with ninth sternite short and only 

 slightly sclerotized, and tenth segment with 

 lateral plates long and slender. 



This species, originally described by Hagen 

 from Chicago specimens, is apparently con- 

 fined in Illinois to the vicinity of Lake 

 Michigan and glacial lakes in the northeast- 

 ern corner of the state. Our records are 

 too incomplete to be sure of the number of 

 generations, but large flights have been 

 taken from May to mid August. It is possi- 

 ble that there is only a single generation 

 and that the late emergence records are 

 from cold water situations. Vorhies (1909, 

 p. 688) reared this species in the lakes 

 around Madison, Wisconsin, and described 

 the larvae and adults. We have taken 

 pupae commonly on stones in Channel Lake 

 near Antioch, Illinois. 



The range of the species apparently in- 

 cludes most of the Northeast, extending 

 westward to Minnesota and south to 

 Georgia. We have records from Georgia, 



