THE PILL BEETLES. 



673 



II. Cytilus Ericlis. (Gr., "covering + mud. ") 



In this genus and the next the head is vertical or bent down- 

 ward, the labrum distinct and fitting close to the front, and the 

 body covered with a line, easily removed pubescence forming varied 

 patterns. Two species of Cytilus are known, both of which occur 

 in Indiana. 



12SS (3887). Cytilus sericeus Forst, Nov. Spec. Insect., 1771. 



Subovate, narrowed in front, strongly convex. Bronzed black, shining ; 

 densely covered with a fine pubescence which, on head and thorax, is nearly 

 uniform bronzed ; on elytra the four or five inner intervals are alternately 

 narrow and uniform metallic green, and wider, slightly elevated, and green 

 tesselated with black. Head and thorax rather finely and densely, elytra 

 more sparsely and coarsely, punctate ; the punctures visible only after the 

 pubescence is removed. Length 5 mm. 



Lake and Warren counties ; frequent along the beach of Lake 

 Michigan. May 28-July 28. 



12S9 (3S88). Cytilus trivittatus Melsh., Proc. Phil. Acad. Nat. Sci., II, 

 1844, 117. 



Resembles the preceding in form and structure but a little larger. Uni- 

 form dull bronze ; thorax with a patch of golden hair at middle of base ; 

 elytra with the alternate intervals slightly elevated and tesselate with 

 squarish black spots. Length 5.5-6.5 mm. 



Lake and Laporte counties, beneath rubbish along the beach of 

 Lake Michigan ; scarce. Taken with sericeus, and may eventually 

 prove to be the female of that species. May 20-May 28. 



III. Byrrhus Linn. 1766. (dr., "a hide.") 



To this genus belong the largest members of the fam- 

 ily. They resemble closely those of Cytilus, but have all 

 the tarsi strongly retractile. Two of the eight known 

 species from North America have been taken in the State. Byrrhus puliusL. 



(Fig. 251.) A European spe- 



1290 (3889). Byrrhus americanus Lee, Agassiz Lake Sup., 1850, 224. 

 Oval, strongly convex, narrowed in front. Black, densely covered with 



fine grayish pubescence; thorax indistinctly marked with gray; elytra each 

 with three or four narrow interrupted black lines and a double, narrow, 

 sinuous gray crossbar at middle. Length 8.5-9.5 mm. 



Lake and Laporte counties, along the beach of Lake Michigan; 

 scarce. May 20-June 10. 



1291 (3895). Byrrhus murinus Fab., Syst. El., I, 1801. 104. 

 Rounded-ovate, strongly convex. Black, closely pubescent and covered 



with numerous short, erect, bristle-like hairs; elytra each with four or five 



