. An illustrated descriptive catalogue of the coleoptera or beetles (exclusive of the Rhynchophora) known to occur in Indiana : with bibliography and descriptions of new species . Beetles. 230 FAMILY 1\. DYTISC' KEY TO INDIANA GENEKA OF DYTISCINI. «. Length one inch or more; joints of hind tarsi not (ringed with flattened hairs on the outer margin, the last one with two claws; trunt tarsi of males with two large and numerous small disks. XIX. I>YTiscrs. «(/. Length exceeding one-half inch; joints of hind tarsi fringed on the outer margin. 6. Spurs of hind tibite acute at ap
. An illustrated descriptive catalogue of the coleoptera or beetles (exclusive of the Rhynchophora) known to occur in Indiana : with bibliography and descriptions of new species . Beetles. 230 FAMILY 1\. DYTISC' KEY TO INDIANA GENEKA OF DYTISCINI. «. Length one inch or more; joints of hind tarsi not (ringed with flattened hairs on the outer margin, the last one with two claws; trunt tarsi of males with two large and numerous small disks. XIX. I>YTiscrs. «(/. Length exceeding one-half inch; joints of hind tarsi fringed on the outer margin. 6. Spurs of hind tibite acute at apex; claws of hind tarsi unequal. XX. Hydaticks. 1)1). Spurs of hind tilii:c emarginate at apex. c. either 4-suIcate (female), or with distinct, clcisely phued. moderate sized punctures (male). XXI. AciLirs. cc. lOlytra not distinctly punctured, sometimes \- finely punetulate or partially aciculate. (/. Jliddle femora with long conspicuous set;c. XXII. (hi. Middle femora with short, stout sette. XXIII. Geaphoi)Kr:s. The emarginate or bifid tips of the tibial spurs in the last thi'ee ueiiera are ver^â fine, and must be looked for with a good lens. XTX. Dytiscus Linn. 1735. (Gr., "a ;) To this genus lielong the largest of our diving beetles. They are of a dark olive-brownish hue, with the elypeus and a .stripe along the sides of thorax and elytra dull yellow; front and hind margins o f thoi'ax also usually more or less yellow. (Fig. 115.) Form elon- gate-oval, little con- vex and of variable width; elypens sepa- rated from head by a suture visible across the full width ef head; thorax not m a r g i n e d ; claws e(| in both sexes. The females of some Fi?. 115. Dytiscui:-a, of D. murginalis devouring a larva of ^Pi'^^'lt'S always liaVC ; 6, pupv of .sime; r, D. fasdKnlris Say; grooved eljlron of ii i . ^ i -i femile; rf, front tarsus of male, under side, showing the suctioncups; r, 1^'''' elytra deeply antl
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectbeetles, bookyear1910
