254 GEO. H. HORN, M. D. 



Group XIII.— CH^TOCNEM^. 



Antennjie 11-jointed. Thorax without trace of ante-ba.sal impres- 

 sion. Elvtra regularly striato-puuctate. Anterior coxal cavities 

 closed behind. Middle and posterior tibise distinctly sinuate on the 

 outer edge near the apex, the sinnation limited above by an angula- 

 tion. Tai'sal claws appendiculate at base. Abdomen with first two 

 segments closely united and immobile, the suture distinct. 



This tribe is sufficiently well characterized among those with closed 

 coxal cavities by the close union of the first two ventral segments. 

 By this character alone it may be distinguished. In our fauna but 

 one genus is known, the species having a facies that will enable it 

 to be recognized without difficulty. 



CHJETOCiVEMA Steph. 



Head inserted in the thorax as far as the eyes, the front flat, not 

 carinate (in our species). Clypeus broadly emarginate, labrum trun- 

 cate. Maxillary palpi rather slender, the second and third joints 

 obconical, the last joint more slender, elongate conical. Antennae 

 slender, at least half the length of the body, slightly thicker exter- 

 nally, first joint clavate, second elongate oval, third to sixth slender 

 and longer, seven to eleven gradually broader and flattened, the 

 terminal joint nearly as long as the two preceding, acute at tip. 

 Thorax always broader than long, usually twice as wide, narrowed 

 in front with but few exceptions, sides regularly arcuate, obliquely 

 truncate at the front angles in some, base i-egularly arcuate. Scutel- 

 liiu) transverse. Elytra at most but little wider than the thorax at 

 base, humeri never prominent, surface striato-punctate. Prosternum 

 moderately wide between the coxte, usually coarsely jjunctate, the 

 apex dilated beliind and with the epimera closing the coxal cavities. 

 Abdomen with the first two segments connate, the suture, however, 

 distinct. Legs moderately long, the middle and posterior tibiae 

 broader below the middle and with a sinuation limited above by a 

 more or less triangular tooth, the posterior tibiie more or less grooved 

 at apex on the outer edge, the margins of the groove ciliate with 

 short hair, and above these more or less denticulate, terminated at 

 apex by a moderately stout and long spur. Tarsi moderate in length, 

 the claw joint simple. Claws appendiculate at base. PI. VII, fig. 9. 



Our species belong to the subdivision Chsetocnema proper as de- 

 fined by Foudras and Chapuis, having the flat front, while in Plec- 

 troscelis the carina is distinct. 



