OF AMERICA NORTH OF MEXICO. 317 



NECYDALIS, Lin. 



aput thorace latius, quadratum, basi subito constrictum. 

 Oculi transversi. 

 Antennse filiformes. 



Elytra valde abbreviata, apice rotundata ; aloe rectse. 

 Corpus filiforme, pedibus tenuibus, postlcis elongatis. 

 N. MELLiTus. — Niger, tenuiter pubescens, thorace punctulato, latitudine longiore, utrlnque profunda 

 constricto, medio carialiculato, elytris alutaceis, parum punctatis, testaceis margine infuscato, medio 

 oblique impressis, abdomine pedibus, antennarumque articulo 1™" rufo testaceis. Long. •48 — 80. 

 % Hald. 44. 



$ Jfecydalis americanits, Hald. 44. 

 Molorchus mellitus, Say. B. J. L. 194; Harris Hartford Tr., 89. 



New York to Georgia and Missouri, rare. Although Mr. Say observed what he 

 has considered as both sexes of this species, I prefer citing N. americanus as the true 

 female. My specimen (taken in coitu with N. mellitus by Mr. Brevoort,) is much 

 larger than the male, but only differs by its black abdomen and shorter antennae. 

 The under surface of the abdomen is rufo-testaceous, as in the male. The abdomen 

 is more acute and less dilated towards the tip. 



ENCYCLOPS, Newman. 



Caput thorace latius, quadratum, basi subito constrictum. 

 Oculi globosi, prominuli, superne subito emarginati. 

 Elytra abdomine baud breviora, apice rotundata. 

 Antennae filiformes. 



Corpus filiforme, pedibus tenuibus, posticis eJongatis. 

 E. C(ERULEUs, — laete viridi-sneus, opacus, thorace reticulato-punctato, antrorsum angustato constrictoque, 



lateribus tuberculato, elytris confertim punctatis, subtus cinereo-pubescens pedibus flavis, antennis 



nigiris. Long. '3. 

 Hald. 1. c. Ap. 375. 

 Lepfura ccendea, Say. J. Ac. 5, 280. 

 Encydops paUipes, Nm. Ent. Mag. 5, 392. 



Middle and Northern States, rare. 



DESMOCERUS, Serv. 



Caput thorace angustius, postice non constrictum. 



Oculi intus valde emarginati. 



Antennse nodosas. 



Elytra abdomine baud breviora, apice rotundata. 



Corpus parallelum, antrorsum anguslatum, pedibus mediocribus. 



The thorax is narrowed in front, with the posterior angles acutely produced. The 

 mesosternum is plane, and triangular, and the tibial spurs are placed at the apex. 



