SCARAB^EIDAE. 1£9 



are pyramidal and short ; the inner lobe of the maxillae is very 

 small, and hooked at the tip; the outer one is larger, but still 

 small, rounded at tip, and hairy; the maxillary palpi are long 

 and slender, the second joint equal to the third and fourth, the 

 third being only half as long as the fourth. The mentura is 

 nearly semicircular; the ligula is entirely concealed by the base 

 of the labial palpi, which are moderate in length, the third joint 

 being as long as the first and second together. The anterior 

 coxa? are large, conical, prominent; the middle ones contiguous, 

 prominent, conical, oblique ; the elytra cover the pygidium almost 

 entirely. The anterior tibiae are 3-toothed, and have two small 

 teeth above the upper tooth; the middle and hind tibiae are ex- 

 panded at tip, and have two acute teeth placed transversely about 

 the middle on the external surface. The tarsi are longer than 

 the tibiae, and slender, the joints 1 — 4 equal, the fifth longer than 

 the two preceding; the claws slender, with a narrow bisetose 

 onychium. Ventral segments free, the sixth retracted within the 

 fifth. 

 Of the habits of this remarkable insect nothing is known. 



Tribe VII.— ACAMHOCERWfl. 



Mandibles and labrum corneous, prominent; antenna? 9- or 10- 

 jointed, club 3-jointed ; anterior coxa? conical, prominent ; middle 

 coxse transverse, contiguous ; epimera of the mesothorax attaining 

 the coxse ; epimera of the metathorax covered ; ventral segments 

 five, not connate ; body 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 by Lacordaire and pre- 

 vious authors as forming a sub-tribe of Trogini ; but the difference 

 iu the side pieces of the mesothorax, which extend to the coxa?, as 

 in all other Scaraba?idae, 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 antenna? : — 

 Body partially contractile ; middle and posterior tibiae thick. 



ACANTIIOCEIUTS. 



Body perfectly contractile ; middle and posterior tibia? compressed. 



SpUiEEOMOKPnUS. 



9 



