896 



FAMILY XLII. — ClOID.E. 



typical genus, Cis, which is from a Greek word meaning "a worm 

 in wood or grain. ' ' The beetles are mostly found under the bark of 

 trees and in dry and woody species of fungi, and are usually 

 gregarious. Some species occur in houses and are injurious in the 

 larval stage to books, furniture and old woodwork, which they 

 pierce with small round holes. The grubs which prey upon books 

 are known as ' 'book- worm s. " 



The principal characters by which the Cioida? may be known are 

 the 8- to 10-jointed antenna? (11 -jointed in one genus), inserted at 

 the front margin cf the eyes, the last three joints larger, forming a 

 loose club; eyes rounded, somewhat granulate; thorax with side 

 margins distinct, cylindrical, rounded in front, and frequently pro- 

 longed over the head. Elytra entirely covering the abdomen, the 

 latter with five free ventral segments, the first longer than the 

 others ; front and middle coxa? oval, not prominent, without troch- 

 antins, the cavities small, separate, narrowly closed behind; legs 

 moderately short; tarsi four-jointed, joints 1-3 very short, equal, 

 fourth long with simple claws. 



The principal available paper treating of the North American 

 species is that by 



Casey. — • ' Studies in the Ptinidoe, Cioida? and Sphindida? of 

 America," in Journ. N. Y. Entom. Soc., VI, 1898, 61-93. 



Of the nine genera recognized by Casey, representatives of seven 

 have been taken in Indiana. 



KEY TO INDIANA GENERA OF CIOID.5C. 



a. Antennae with last three joints larger, forming a loose club. 

 7?. Antenna? 10-jointed. 



c. Prosternum simple or nearly so. 

 d. Body with distinct erect bristly hairs; front tibia? usually pro- 

 duced and toothed on outer side at apex. I. Cis. 

 dd. Body glabrous or minutely pubescent ; front tibia? not toothed 

 or produced ; body elongate ; head and thorax simple in male. 



II. Orthocis. 



cc. Prosternum carinate along the middle ; body either glabrous or 

 with short decumbent pubescence. III. Xestocts. 



1)1). Antenna? 8- or 9-jointed; body glabrous. 



e. Front tibia? thickened and rounded on the outer side. 

 f. Antennae 9-jointed ; body narrow, cylindrical. 



IV. Ennearthron. 



//. Antenna? 8- jointed. V. Ceracis. 



ee. Front tibia? narrowly triangular, the outer edge straight and 

 minutely spinulose; antenna? 8-jointed. VI. Octotemntjs. 



aa. Antenna? with joints 5 to 11 forming a large pectinate mass, 11-jointed ; 

 elytra silicate. - VII. Rhipidandrus. 



