SCARAB^RIDAE. 245 



Tribe VII.— ACAiXTHOCKRIIVI. 



Mandibles and labruui corneous, [)roniiiient ; anteiinte 9- or 10- 

 jointed, club o-jointed; anterior coxaj conical, proniincnL ; middle 

 coxce transverse, contiguous; epimera of the niesothorax attaining 

 the coxJB ; epimera of the nietathorax covered; ventral segments 

 five, not connate; bod}' contractile into a ball; pygidium entirely 

 covered by the elytra; tarsi with slender claws and no onychium. 



Oval, convex, smooth, shining insects, living under bark and 

 in rotten wood. They have been considered b}' Lacordaire and 

 previous authors as forming a sub-tribe of Trogini ; but the differ- 

 ence in the side pieces of the mesothorax, which extend to the 

 coxas, as in all other Scarabaiidse, requires them to be separated. 

 Other differences are found in the large size of the scutellum, and 

 the tarsi fringed with long hairs. 



Our genera are two, both having 10-jointed antennae: — 



Body partially contractile ; middle and posterior tibiffi thick. Cloeotus. 

 Body perfectly contractile; middle and posterior tibiae compressed. 



Sphaeromorphus. 



Two species of the first genus, and one of the second, are found 

 in the Atlantic States. 



Tribe VIII.— IVICAGIiVI. 



Nicagus obf^curus {Ochodseus obscitrus Lee.) is the only mem- 

 ber of this tribe known. It is an oval, convex insect, more than 

 a quarter of an inch long, brown, densely punctured, ami covered 

 with very short pale hair. It resembles in appearance some of 

 the Serica3, or a nearly smooth Trox. It is found throughout the 

 Atlantic district. 



The head is rounded, moderately convex, the front finely mar- 

 gined; the labrura is broadly rounded, hairy; the mandibles short, 

 pyramidal, not very prominent; the mentum is thick, triangular, 

 hairy, pointed in front; the palpi short, the last joint oval. The 

 antennae are 10-jointed, the club 3-jointed, longer in the nnile 

 than in the female. The anterior coxa? arc large, conical, i)romi- 

 nent ; the middle ones nearly contiguous, oblique ; the epimera 

 of the mesothorax attain the coxa;. The elytra cover the pygi- 

 dium. The abdomen has five free ventral segments. The legs 

 are normal in form; the anterior til>i;e are 4-toothed, the middle 

 and hind ones gradually thickened towards the tij) in the female, 



