THE LAMELLICORN BEETLES. 



913 



Fig. 360. Canthon Icevis Drury. Male and 

 female at work rolling a ball of dung. 



able distance, the long, slender, slightly curved hind tibiae having 

 become modified and well adapted for 

 this work. The beetles work in pairs, 

 a male and a female together, and the 

 ball which they roll is often several 

 times as large as their combined size. 

 (Fig. 360.) They finally bury the 

 ball in the ground and the female 

 then deposits an egg in one side of it, 

 thus insuring the future larva a suit- 

 able supply of food. Comstock says 

 that "this is one of the instances, 

 rare among insects, where the male 

 realizes that he has some responsibil- 

 ity as a father, and assists the female 

 in providing for the young. This 



strange habit of rolling these balls has occasioned much speculation 

 as to its object, and has been the source of many superstitions, espe- 

 cially in ancient times. The only reasonable theory that we have 

 met is that, as many predaceous insects frequent the masses of dung 

 from which the balls are obtained, in order to prey upon the larvae 

 which live there, the more intelligent tumble-bugs remove the food 

 for their larvae to a safe distance." The sexes of Canthon are alike 

 in appearance and the clypeus has prominent teeth at the middle. 

 Five species have been taken in Indiana, while four others may 

 occur. 



KEY TO INDIANA SPECIES OF CANTHON. 



a. Sides of thorax beneath without an entire transverse carina. 



7). Clypeus with four to six teeth ; hind thighs not margined in front ; 

 size small or medium. 6 to 10 mm. ; color black, 

 c. Hind tibiae with two spurs. 1723. nigricoknis. 



cc. Hind tibiae with one spur. 



d. Subhumeral stria not carinate ; surface coarsely granulate. 



e. Hind femora with bristle-bearing punctures ; thorax more 

 coarsely granulate. ebenus. 

 ce. Hind femora with fine setae, sparsely punctate ; thorax more 

 densely, much less coarsely granulate. depressipennis. 

 (hi. Subhumeral stria carinate ; surface not granulate, very smooth, 

 almost shining. probus. 

 bh. Clypeus with two teeth ; hind thighs margined in front; size larger. 

 11-22 mm. 



f. Eyes larger ; antennae reddish-brown. yigilans. 

 //. Eyes smaller ; antennae dark brown. 



g. Thorax distinctly granulate; pyg'idium and last ventral segment 

 granulate. 1721. l.evis. 



