9Hfi I'^AMILY L. SClAEAB.-ErD.13. 



Tribe IV. GBOTRUPINI. 



Bounded, convex beetles having the mandibles and labrum 

 prominent, of horn-like texture ; antennas llT.jointed, club 3-jointed, 

 variable in form ; elytra visually strongly striate, covering the abdo- 

 men ; the middle coxa?, ventral segments and tarsal claws as in Tribe 

 Til. The thorax of some males, and more rarely the head, is armed 

 with horns oi- tiil)('rc]os. i\lost of the species live in excrement; 

 others, according to Horn, are veritable hoboes, "wandering about 

 without visible means of suiiport." The princip;d literature treat- 

 ing of the North American meml)ers of the tribe is as foll(jws: 



Horn. — "Notes on Oenera of Coprophagus Scarabfeidas of the 



IT, S.," ht Trans. Amer. Ent. Soc., Ill, 1870. The genera 



Bradnciiieiiif., BoUiocoris and Odoirtd'us are treated on pp. 



48-50. 



Ilont. — "G-eotrupes of Boreal America," in Trans. Amer. Ent. 



Soc, I, 1868, 313-322. 

 Tliirn. — "Synopsis of the G-eotrupes of the U. S.," in Trans. 



Amer. Ent. Soc, VIII, 1880, 145. 

 Dlaiicharti. Frcderir];. — "Some account of our Species of Geo- 



trupes," in Psyche, V, 1888', 103-110. 

 Scltirffcr, C'has. — "On Bradyeinetus and Bolboceras of North 

 America, with Notes on other Genera," in Trans. Amer. Ent. 

 Soc, XXXII, 1906, 249-278. 

 Of the five genera of Geotrupini recognized from the United 

 States, representatives of four have been taken in Indiana: 



KEY TO IXDIANA GENERA OF GEOTRUPINI. 



a. Club of aiitemifB large, round, convex on both sides. (Fig. j, x,,. u.) 

 6. p;y('s only partially divided by a process from tlie side of bend. 



XII. liDLHOCERAS. 



hh. Eyes entirely divided. 



c. ("olor above black and reddish-brown; process between the middle 

 coxre with an erect tooth-like elevation. 



XIII. BOLBOCEROSOMA. 



cc. Color above uniform chestnut Iirown ; process lielween the middle 



coxir without a tooth-like elevation. XIV. Odoxt.evs. 



00. Cilubofantennaj smaller, composed of leaf-like plates. XV. GEOTmPES. 



XTI. Boi.BOCERAS Kirby. 1S18. (Gr., "bulU horn.") 

 This genus is principall>- distinguished by having the eyes only 

 partly divided and l,y the middle coxffi being continguous'or very 

 close together. 



