864 



FAMILY XLIII. PTINTMC. 



Subfamily I. PTININAE. 



Our members of this subfamily are small-sized species having 

 the antennae inserted on the front and more or less approximate at 

 base, rather long and moderately stout, filiform or feebly serrate. 

 11- jointed. Head and thorax small, the latter without side mar- 

 gins, the disk frequently swollen or tubereulate. Elytra much 

 wider than thorax, usually oval or globose. Legs long, not con- 

 tractile, with trochanters in the axils of the thighs ; tibia? with two 

 small or minute terminal spurs; tarsal claws simple, strongly di- 

 vergent. Representatives of but two of the eight genera have as 

 yet been taken in Indiana, though those of one other should occur. 



KEY TO INDIANA GENEBA OF PTININ.E. 



a. Elytra not punctured, polished, widely embracing the abdomen at the 

 sides; ventral surface about one-third the width of elytra. 

 h. Head and thorax entirely glabrous; eyes subfrontal; ventral seg- 

 ments four. Gibbium. 

 1)1). Head and thorax densely covered with small scales and scale-like 

 hairs ; eyes on sides of head ; thorax tubereulate ; ventral segments 

 five. I. Mezium. 



aa. Elytra with rows of punctures, pubescent, much less widely embracing 

 the abdomen, parallel in males, oval in some females; ventral sur- 

 face nearly equal in width to elytra ; eyes large ; thorax strongly con- 

 stricted behind. II. Ptinus. 



Gibbium psylloides Czemp., upper surface glabrous, under sur- 

 face with dense short, yellowish hairs, occurs in houses from Vir- 

 ginia to California. 



I. Mezium Curtis. 1828. 



Small species having the eyes very small, elliptical, flat and 

 widely separated; entire surface except the elytra densely clothed 

 with pale yellow scales and scale-like hairs; elytra smooth, much 

 inflated, highly polished; last antennal joint but little longer than 

 tenth, oval, pointed; ventral surface greatly contracted, segments 

 one to four short ; fifth equal to all the preceding united. One 

 species occurs throughout the United States. 



1649 (5236). Mezium amekicanum Lap.. Hist. Nat. des Coleop., I, 1837, 

 297. 



Oval, the elytra subglobose. Dull yellow ; elytra piceous, shining. Tho- 

 rax subcylindrical, sulcate on middle of disk, sides with obtuse tubercles. 

 Elytra very smooth, highly polished. Length 2.5-3 mm. 



Marion County; rare. June 20. A single specimen from box 

 which had contained dried insects. Occurs in houses, where it is 

 said to breed in all sorts of dried animal substances. 



