238 



FAMILY v.— GYKIXID.E. 



"0. Last ventral elongate, conical; lal.r.un pnanlnent; scntellum invisible- 

 length 6 mm. 



Gyketes. 



1. Gyrinlts Linn. ITMl (Cr.. "a circle or ring.") 



Our inemhers of this genus are smaller, more 

 nari-()\\- and more convex than those of the next. 

 'Ilicy have cloven rows of distinct punctures on 

 *''!'•'' ''l.vtnMi which, when 1,..1,1 in a certain light 

 nsually .vilocl a gohlcn 1 inl ; 1 h.> legs are ahN'iivs 

 reddish-hrown or yellowisli in hue. (Fig. 12]".) 

 On account of the close resemblance between the 

 species, their definition and recognition is quite 

 difficult. The follomng have been taken or per- 

 haps occur in Indiana. 



Fig. 121. i, beetle; 2, larva, 

 (After I'ackard.) 



4G3. MINUTUS. 



KEY TO INDIANA SPECIES OF GYRINUS. 



". Scntellnm finely bnt distinctly cariuate 

 int. Scntellum flat. 



Ik Under side margin of thorax an.l epiplcnra hrownish-vellow 

 r. Under snrface uniform brown or brownish-vellow ' 

 (I. Larger, G-7 mm. 



e. Polished black, not bron.e.l or iridescent. 4G4. eraternus 



''. Llaek, very Ingbly iridescent, .nargins and sides bronzed. 



. lii,s Of e ytra romuled ; f..,n, broader. 4(15. ventraeis. 



//. lips ot elytra trtm.-ate: form n.on> narrow. Aornus 



'/'/. Smaller, 4.5-5.5 mm. ai;i nus. 



.'/. Form more elongate; tips of elytn, rounded, covering onlv half 



ot last ventral segment. 



h. Margins, sides and snlnre of ..jytra ,listin.-(]y bronzed. 



nil. Llytra not at all bronzed. 4cv „ 



... Form Short, broad; tips of elytra nearly trnn:!:;. ^H: 

 rr TT I l^ ''''''^'''''^ ^^"^ ^""^ ''''''^'^^ '^^S^^^^t. 4G,S. EiMBvrus 



• "r^r:::^ "•" - ^"--- — = -- — «t re. 



i. Upper surface finely alutaceous; length 7-S mm. 469. aeeinis 

 n. Upper surface not alutaceous ; length 5.5 mm. 470. piceoi r 

 "1.. Under side margin of thorax and epipleura metallic black 

 ./. t ront margin of mesosternum regular in form. 

 /.-. Flytra highly polished, distinctly brouzed 



/. Smaller and more narrow. 5-6 mm.; 'outer rows of elytral 

 punctures but little stronger than inner. 471 anaus 



dlS^r '"^'"••7 """-^ "•"^''- ^'^-^ ^'^ elytral punS::;^ 

 distinctly impressed. ,^r, 



7.7,. Flvti-o M.wl , '^'~- BOREALIS. 



U.. Elytia black, scarcely polished and not nt all bnmzed. 



././. Front margin .,fmesosfernnn, I rilobc.l uiti, -,„ 1 c ^"^' ^^'''^''^■ 

 t^^,.h ^in . , '""""""*•'• \\'' I' .-III oblKine impress on 



each side: under sni-fjirc bl'ick- i..i..,-fi, - ,• 



"i.K K. length ., (, mm. pectoraeis. 



