212 
canadense, Stenonema interpunctatum, 164 
canadensis, Baetis, 107, 164 
candidum, Stenonema, 156, 159, 161, 162 
carolina, Heptagenia, 161 
carolina, Hexagenia, 41 
carolina, Stenonema, 156, 159, 161 
centralis, Pseudiron, 4, 145, 149 
Centroptilum, 114, 119, 120, 143 
Chirotenetes, 109 
Chirotonetes, 109 
Chitono phora, 56 
Choroterpes, 84, 95 
cingulatus, Baetis, 125, 126, 133 
Cinygma, 153, 154, 176, 196 
Cinygmula, 152, 154, 154, 176, 195, 196 
circumfluus, Campsurus, 30 
cleptis, Baetis, 122, 124, 125, 130, 131 
Cloe, 141 
Cloea, 141 
Cloeon, 8, 98, 114, 140, 141, 143 
Cloeopsis, 141 
columbiae, Parameletus, 107, 103 
concinna, Palingenia, 86 
concinnata, Ephemerella, 69 
conjunctum, Stenonema, 164 
consimilis, Ephemerella, 15, 16, 57 
Cora, 20 
cornuta, Ephemerella, 57, 59, 62, 62, 63, 65 
cornutella, Ephemerella, 57, 59, 62, 62, 65 
coxalis, Ephemerella, 60, 61, 63, 64, 73 
croesus, Parameletus, 103 
cruentata, Heptagenia, 15, 181, 782, 188 
cupida, Ephemera, 86 
cupida, Leptophlebia, 5, 6, 82, 85, 86 
cupidus, Potamanthus, 16 
curiosum, Baetis (Acentrella), 121 
curiosum, Centroptilum, 121 
curiosum, Heterocloeon, 115, 121, 121 
D 
dardanus, Baetis, 126 
debilis, Baetis, 16, 180 
debilis, Baetis, 90 
debilis, Paraleptophlebia, 38, 89, 90 
decoloratus, Campsurus, 30 
decora, Ephemera, 36, 37 
deficiens, Ephemerella, 58, 59, 62, 64, 67 
diabasia, Heptagenia, 153, 179, 181, 182, 183, 
183, 184, 185, 187 
diminuta, Caenis, 46, 51 
diptera, Ephemera, 142 
dipterum, Cloeon, 9, 141, 142 
distinctus, Potamanthus, 31, 37, 32 
diversa, Isonychia, 109, 770, 111 
dorothea, Ephemerella, 4, 58, 59, 63, 70 
Drunella, 56 
dubia, Cloe, 15 
dubia, Cloe, 137 
dubium, Cloeon, 143 
dubium, Pseudocloeon, 4, 5, 137 
E 
Eatonella, 56 
Ecdyonuridae, 21, 144, 151 
Ecdyonurus, 155 
Ecdyurini, 21 
Ecdyurus, 155 
ILLiInoIs NATURAL History SurvEY BULLETIN 
Vol. 26, Art. 1 
elachistus, Baetis, 722, 123, 124, 127 
elegans, Hexagenia, 41 
elegantula, Heptagenia, 181, 104 
Epeorus, 152, 153, 154, 176, 194, 195 
Ephemera, 35, 38 
Ephemerella, 8, 11, 45, 55, 56, 57, 58, 59, 146, 
180 
Ephemerellidae, 21, 22, 26, 55, 56 
Ephemerellinae, 22, 55 
Ephemerellini, 21 : 
Ephemeridae, 8, 10, 20, 21, 22, 26, 27, 35, 37, 42, 
55 
Ephemerinae, 20, 21, 22, 28, 35 
Ephemerini, 20, 21 
Ephemeroidea, 21 
Ephoron, 7, 8, 27, 32, 33 
Ephoroninae, 21, 22, 28, 32 
erebus, Baetis, 130, 131 
Euphyurus, 84 
Eurycaenis, 48 
excrucians, Ephemerella, 15, 16, 58, 59, 60, 63, 
70 
excrucians, Ephemerella, 67 
F 
falcata, Hexagenia bilineata, 39, 41 
feminina, Ephemerella, 71 
femorata, Baetis, 15 
femorata, Baetis, 106, 150, 169 
femoratum, Stenonema, 157, 159, 161, 163, 169 — 
femoratum, Stenonema femoratum, 169 
ferruginea, Cloe, 15 
ferruginea, Cloe, 117 
ferrugineus, Callibaetis, 5, 99, 115, 116, 117, 
118, 118 
flaveola, Ephemera, 15 
flaveola, Ephemera, 31, 32 
flavescens, Heptagenia, 181, 782, 183, 186, 136, 
187 
flavescens, Palingenia, 15 
flavescens, Palingenia, 187 
flavistriga, Baetis, 175, 125, 126, 133 
flexus, Siphlurus, 150 
fluctuans, Callibaetis, 5, 23, 99, 115, 116 
fluctuans, Cloe, 15 
fluctuans, Cloe, 116 
forcipata, Caenis, 46, 51, 54 
fratercula, Ephemerella, 58, 60, 71 
frisoni, Ephemerella, 4, 57, 59, 63, 64, 65, 66 
frivolus, Baetis, 123, 124, 127 
frondalis, Baetis, 4, 175, 122, 124, 125, 126, 128, 
129 
frontale, Stenonema, 156, 159, 161, 165 
frontale, Stenonema interpunctatum, 162, 164 
frontale, Stenonema interpunctatum, 165 
frontalis, Heptagenia, 165 
funeralis, Ephemerella, 61, 61, 64, 75 
fusca, Heptagenia, 173 
fuscata, Baetis, 65 
fuscata, Ephemerella, 65 
fuscum, Stenonema, 157, 160, 161, 173 
G 
gigas, Caenis, #6, 51, 53 
gildersleevei, Stenonema, 156, 159, 161, 163 
gracilis, Blasturus, 5 
grandis, Ecdyurus, 185 
