(EDEMERIDAE — CEPHALOIDAE. 250 



Penultimate joint only of the tarsi spongy pubescent beneath ; ante- 

 rior tibiffi with two spurs. Asclera. 



Calopus is found in Texas and New Mexico ; the other genera 

 are represented on both sides of the Continent ; the only species 

 of Nacerdes is N. melanura, which is also found in Europe. 



Microtonus is founded on a very small brown sericeous insect, 

 found on leaves in the Atlantic States. The last joint of the 

 palpi is large and securiform ; the antennae are inserted at a small 

 emargination of the eyes, are slender, one-half the length of the 

 body, with the 2d joint one-third as long as the following one ; 

 the eyes are comparatively large, widely separated, and tolerably 

 coarsely granulated ; the front is crossed by a very distinct curved 

 suture, just before the eyes ; the penultimate joint of the tarsi is 

 very slightly bilobed. The species M. sericans Lee. is small 

 (•10—15 unc. long) and slender, brown, densely punctured, and 

 clothed with short sericeous pubescence ; the thorax is as wide as 

 the head, nearly square, feebly bisinuate at base, with the hind 

 angles subacute, very feebly rounded on the sides, and generally 

 vaguely impressed near the sides behind the middle. 



Fam. LVL— CEPHALOIDAE. 



Mentum small, nearly square, supported by a gular pro- 

 cess ; ligula membranous, broad, bilobed, prominent ; labial 

 palpi small, 3-jointed. 



Maxillae with the base large and prominent, and two long 

 slender lobes ciliate at the tip ; palpi 4-jointed, last joint tri- 

 angular, obliquely truncate. 



Head inclined, large, rhomboidal, gradually narrowed be- 

 hind the eyes, suddenly constricted at base, inserted into the 

 thorax by a not very slender neck; eyes small, reniform, 

 finely granulated ; mandibles small, acute at tip, subserrate 

 on the inner margin with a broad membrane extending from 

 the base half the length ; labrum prominent ; frontal suture 

 not distinct. 



Antennae inserted at the sides of the front, under a small 

 ridge in front of the eyes, 11-jointed; slightly thickened to- 

 wards the tip. 



Prothorax elongate, trapezoidal, as wide at base as the 

 elytra, lateral suture wanting; coxal cavities large, confluent, 

 open behind. 



