THE WATER SCAVENGER BEETLES. 259 



500 *(1G14). r.KUOSis STKIATLS JSuy. Jtmni. IMiil. Acad. Nat. Sci., V. ISli.j. 



ISS. 

 Elonirate-oval. coiivox. Mead as iu itcrcuriints but without iinpressiuu 

 iHtwoon the eyes; thorax ami elytra dull i^reeuish-yelluw. the I'ornier with 

 a (l.iul)le luscous line on disk; each elytron with eight or ten small, remote, 

 iudistincl blackish siKits. Elytral stria' distinctly impressed, finely punc- 

 tate; intervals Hat. with rather coarse punctures. Lchl;!]! 1 ~> nun. 



Throughout the State; eonimou. Fehnian 2(i-C)et()ber 21. Hi- 

 l)ernates as imago, specimens having been taken in February from 

 beneath log buried deeply in sand. \vtiil(> olhers were dredged from 

 a pond in early jMarch. 



B. pugnax Lee., 5-6 ram. in length, and colored much as in 

 panthcri)tus, is known from Illinois and Missouri. B. exiguus Say, 

 2.5 in length, occurs from Pennsylvania to Louisiana. 



IX. Ch.etarthria Stephens. 1882. (Or., "bristle + .ioint.") 



Very small species having the first joint of antenmo long and the 

 liody conti-actile. They occur about the margins of ponds and lakes. 



501 (1G19). Ch.etartiiria pallida Lee. I'roc. I'hil. Acad. Nat. Sci.. ISGl, 



342. 



Hemispherical, very convex, shining. Above dull brownish-yellow; head 

 black, shining; disk of thorax often with a fuscous blotch; beneath black. 

 Elytra very sparsely and finely punctate; sutural striae distinct. Length 

 2 mm. 



Lakes of Laporte, Marshall, Fulton, and Starke counties; fre- 

 quent. June 16-August 31. A member of the boreal fauna. This 

 is the form described as nigriceps Lee. 



X. Laccobius Er. 1832. (Gr.. "pool or lake + life.") 



502 (1G21). Laccobius agilis Hand., Bost. .Tourn. Nat. Mist.. II, iS3.S. 10. 

 Subrotund. convex. Head and disk of thorax blackish-iridescent, the 



margins of latter bi-oadly pale j^ellow ; elytra i)ale. the stritne dusky ; under 

 surface black, legs pale. Head alutaceous, finely and sparsely punctate, 

 the margin in front of eyes yellow. Thorax three times as wide as long, 

 as wide at base as elytra, finely and sparsely punctate. Punctures of ely- 

 tra very small and close-set in regular rows. Length 2-3 mm. 



Throughout the State; common. ^iMay 26-September 3 



XI. PniLiiYDRrs Sol. 1834. (Gr.. "love + water.") 



Small oblong-oval beetles, piceous or dull browuish-yelloAV in 

 hue and having the upper surface regularly and rather finely and 

 closely punctured; elytr;i willi four rows of coarser ]mnctures. these 



