310 LAMELLICOENIA. 



species, the sides of the thorax being sinuated behind to the distinct though obtuse 

 hind angles, and the mandibles differing from those of C. mafaffa and allies in being 

 gradually narrowed to the apex. The sides of the elytra in the female are simple, as in 

 the males of the genus. 



33. Cyclocephala melane. 



Oblonga, mediocriter convexa, nigra, nitida, antennis palpisque rufo-piceis ; clypeo sat elongato trapezoidali, 

 angulis anticis rotundatis, margine antico sinuato, hand dense ruguloso, fronte grosse punctata spatiis 

 laevibus ; thorace sparsissime punctulato, antice et lateribus punctis nonnullis grossis setiferis, basi acute 

 marginato angulisque posticis distinctis sed obtusis, lateribus versus angulos posticos parum rotundatis ; 

 elytris sat grosse et regulariter punctato-striatis, versus latera et apicem lineatim setifero-punctatis ; 

 pygidio ( c? ) convexo, punctato et longe rufo-piloso. Prosterni processus postcoxalis tuberculo supra magno 

 rotundato. Mandibulas quam clypeus baud breviores, apice extus hamatas. Mentum sicut in C. mafaffa, 

 antice angustato ligula apice rotundata. Antennas 10-articulatas. Tibiae anticae dentibus approximatis 

 apicalibus duobus ; tarsi antici ( d 1 ) ungue majore fisso. 



Long. 22 millim. S • 



Hah. Costa Rica {coll. Bates). 



One male example. Allied to C. variolosa, Burm., with which it agrees in the 

 margined base of the thorax ; but it is more parallel-sided and of a deeper black 

 colour, and the clypeus is longer. It deceptively resembles at first sight C. nigerrima, 

 from which it differs so greatly in the length of the mandibles and in the form of the 

 ligular part of the mentum. 



V. Clypeus antice sinuatus vel triflexuosus ; mentum apice 

 latissimum, recte truncatum. 



34. Cyclocephala nigerrima. (Tab. XVIII. fig. 12, s .) 



Elongata, oblongo-ovata, nigerrima, polita, pectore, pedibus abdominisque lateribus baud dense vulpino-pilosis ; 

 clypeo magno subquadrato, antice leviter angustato, angulis distinctis, margine antico mediocriter reflexo, 

 subsinuato, cum vertice sparsim punctulato ; thorace subtilissime et sparsissime punctulato, angulis 

 posticis distinctis sed obtusissimis, basi emarginato ; elytris plerumque fere lsevibus politis, interdum 

 punctulatis et geminato-striatis. S • Pygidium convexo, sat fortiter discrete setifero-punctato ; tibiae 

 anticae tridentataB, dente superiore parvo et subremoto : tarsi antici ungue majore profunde fisso. 5 . 

 Pygidium recte declive punctatum, glabrum ; tibiae anticaa acute tridentatae ; elytra medio gradatim leviter 

 dilatata ibique margine incrassato. Mandibulae quam clypeus multo breviores, apice obtuse acuminatae. 

 Ligula lata, subconcava, apice fere recta. 



Long. 22-25 millim. rf $ . 



Hah. Costa Rica (Van Patten), Volcan de Irazu 6000 to 7000 feet, R. Sucio 

 (Bogers). 



A large number of examples. Closely allied to the following, C. ampliata, notwith- 

 standing the different outline of the clypeus. Although coming within the definition 

 of Burmeister's section " Cyclocephala? sinuatse " the sinuation of the clypeus is 

 different from that of C. mafaffa and its allies, being a gradual incurvation from angle 



