342 
[These specimens were originally recorded 
by Hoppe (1938) under the name Chloroperla 
cydippe Newman. | 
Onrario.—Costello Lake, ALGONQUIN PARK, 
Ontario Fisheries Research Laboratory: Sta- 
tion 3, June 2, 1938, W. M. Sprules, 39 ; Sta- 
tion, 3, June 17, 1939, 19% June. 6, 19359 on 
June 8 1939, 19; Station 4, June 12, 1939, 
12; Statione6, June: 7,21939) 1¢ | June 15, 
1939. 10> June. 6; 1939; 2c. Station 7, June 
Oo oat oe | 
TENNESSEE.— GATLINBURG: Fighting Creek, 
branch of Little Pigeon River, May 27, 1934, 
TH. Frison; $4, 2 9% Little Pigeon River, 
[cite BUR ene debe Yabo INeey VO. Le> Conte 
Creek, May 14, 1939, Frison & Ross, Leena s 
Le Conte Creek, June 14, 1940, T. H. Frison 
et al. 66, 323; Pigeon River, June 14, 1940, 
T. H. Frison et al.,.19; June 14, 1940, T. H. 
Frison et al., 19. PAarksviLLe: April 25, 1938, 
Ross & Burks, 6 6, 9 @. PiczON Force: May 
13, 1939, Frison & Ross, 1g. TOWNSEND, Lynn- 
camp Prong, Little River: May 15, 1939, 
Frison & Ross, 14. 
VIRGINIA.—CuRLEY’s NECK BripcE: April 19, 
1938, M. E. Davis & D. T. RiéS5.6.5,.2:9 
WISCONSIN.—BLOOMER: June 5, 1936, Frison 
& Ross, 26, 72. Haywarp, Teal Creek: Aug. 
5, 1932, T. H. Frison, 1¢. SPOONER, Nama- 
kagon River: June 5, 1936, Frison & Ross, 
2 exuviae. Trout LAKE: July 22, 1937, Frison 
Se Ross. house ve 
Alloperla caudata Frison 
Alloperla caudata Frison 
Original description, ¢, 2. 
(19344 “pies 
It is a source of satisfaction now to add 
to the Illinois list of stoneflies the species 
caudata, originally described from mate- 
rial collected in Oklahoma. Specimens of 
this species were first found in Illinois in 
1939, after persistent field work in a small 
stream in southwestern IlJlinois long sus- 
pected of harboring some aquatic insects 
of rare occurrence in this state. In 1940, 
more thorough collecting and better sea- 
sonal timing produced numerous addition- 
al specimens of this species. 
Although caudata is new to the Illinois 
list of stoneflies, there is no need to re- 
describe it. I do, however, wish to present 
as an aid to identification new and better 
illustrations, based mostly upon Illinois 
specimens, of the terminal abdominal seg- 
ments of the male showing the supra- 
anal process and the subgenital plate of 
the female, fig. 121. Fig. 117 shows the 
wing. 
The nymphs of the different species of 
Alloperla described to date, and others 
collected by me, are homogeneous in ap- 
pearance, and caudata is no exception to 
IuLtrnois NATURAL History SURVEY BULLETIN 
Vol. 22, Arta 
this statement. Perhaps careful studies of 
reared material will eventually reveal 
some minute characters which will serve 
to distinguish some or all of the species 
of this genus. As in the case of Allocap- 
nia, Nemoura, Leuctra and other genera 
which have homogeneous nymphs, it 1s 
sometimes possible to identify last stage 
nymphs because the color patterns and im- 
portant genitalic features of the adults 
about to emerge are visible and recogniz- 
able through the nymphal skin. 
A brief description of the. nymph of 
caudata is as follows. 
Nympu.—General color of head, tho- 
rax, abdomen and appendages pale brown, 
without conspicuous bands, spots or stripes 
of contrasting colors, fig. 122. 
Head with three ocelli forming a nearly 
equilateral triangle; distance between 
NyMPHAL 
MANDIBLES 
G ABDOMINAL SEGM 
Fig. 121—Alloperla caudata. 
