. Bulletin. Natural history; Natural history. 148 Illinois Natural History Survey Bulletin Vol. 26, Art. 1 tach front w innpad, niesosternum with hoolc- likc prujcctiun in center of basisternum, middle tenuir as Um^ as tibia and tarsus w ithout claw, middle tarsal claw lonj:, slen- der, more than twice as lonji as middle tibia;. Fi^. 313.—Metreturiis pecatonica, labrum of nymph. Fig. 314.—Mctreturus pecatonica, mandible of nymph. Fig. 315.—Metreturus pecatonica, labium of nymph. Fig. 316.—Mctrrturus pecatonica, maxilla of nymph. metasternum with hooklike projection in the center, hind femur on
. Bulletin. Natural history; Natural history. 148 Illinois Natural History Survey Bulletin Vol. 26, Art. 1 tach front w innpad, niesosternum with hoolc- likc prujcctiun in center of basisternum, middle tenuir as Um^ as tibia and tarsus w ithout claw, middle tarsal claw lonj:, slen- der, more than twice as lonji as middle tibia;. Fi^. 313.—Metreturiis pecatonica, labrum of nymph. Fig. 314.—Mctreturus pecatonica, mandible of nymph. Fig. 315.—Metreturus pecatonica, labium of nymph. Fig. 316.—Mctrrturus pecatonica, maxilla of nymph. metasternum with hooklike projection in the center, hind femur one and one-half times as long as tibia and tarsus without claw, hind tarsal claw five times as long as tibia. Abdomen three times as long as , tapering toward posterior end, so that segment 9 is two-fifths as wide as seg- ment 1 ; prominent, flat flange and projecting, posterolateral angle present at each lateral margin of tergites 1-9; a hooklike projection present in center of each tergite 1-9, with a small, median papilla present at posterior margin of each of these tergites; segments 1-7 each bearing a pair of gills, each gill composed of a dorsal member, with a re- curved ventral flap, and a ventral member, each gill member having a stout, median tracheal trunk from which arise numerous, pinnately branching tracheae; lamina of gill partly eroded away between these tracheae, so that ventral member of each gill almost assumes appearance of a cluster of branch- ing filaments; nearly all or smaller part of upper member of each gill having a similar appearance, this atrophy of gill lamina of upper member almost complete in first gill, but becoming progressively less so in more posterior gills, the upper member of seventh gill with lamina eroded only at apex and on mesal side; caudal filaments alternately banded with faint yellow and light brown. Holotype, female nymph. — Taken by seining in Sugar River, one-fourth mile above mouth, near Harrison, Illinois, July
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Keywords: ., booka, bookcentury1900, bookdecade1910, booksubjectnaturalhistory
