HYMENOPTERA. 281 







of the antennae black, the flagellum ferruginous beneath, fuscous 

 above ; the margin of the prothorax has a line of white pubes- 

 cence, a similar one encircles the tubercles, another forms an 

 epaulet over the tegulae, a central one terminates on the disk and 

 has an indistinct spot on each side of the same colour ; on the 

 scutellum are two raised conical tubercles ; the wings dark fus- 

 cous, the nervures black ; the legs have a black pubescence ; the 

 calcaria at the apex of the intermediate tibiae have two large spines 

 at their extremity, the anterior spine having three sharp denticula- 

 tions within, the apex of the basal joint of the intermediate tarsi 

 produced into an obtuse spine. Abdomen of a metallic green, 

 covered above with minute scales ; the extreme lateral margins 

 of the segments covered with short white pubescence ; the ven- 

 tral plates have laterally on their posterior margins an angular 

 patch of white, and the apical one an elevated longitudinal 

 carina. 



The male closely resembles the female, the antennae are of the 

 same length, the spur on the intermediate tibiae is similar, but 

 the abdomen is shorter, being incurved, the apical segment being 

 subacute and notched in the middle. The posterior legs are more 

 elongate than in the female, the femora and tibiae beneath being 

 naked, polished and concave; the tibiae at their apex beneath 

 have a brush of short stiff hairs, and the basal joint of the tarsi 

 within has a clothing of the same. 



Hab. Brazil (Santarem). (H. W. Bates.) 



4. MELISSA ORNATA. 



Mesocheira ornata, Spin. Ann. Soc. Ent. Fr. x. 145. 96 (1841). 



Hab. Cayenne. 



Genus 35. MESOCHEIRA. 



Maxillary palpi obsolete, or rudimentary, consisting of a small 

 tubercle; the labial palpi four-jointed, the mentum short, broadest 

 at the base ; the first joint of the labial palpi longer than the 

 mentum, the second of about one-third the length of the first, the 

 two apical joints minute, placed on the side near the apex of the 

 seco d joint. The superior wings having one marginal and 

 three submarginal cells ; the former not quite the length of the 

 three latter, rounded at its apex ; the second cell subquadrate, 

 slightly constricted, and the third considerably so, towards the 

 marginal. The intermediate tibiae furnished with a single spine, 

 its apex bifid, the anterior tooth bidentate within ; the spines at 

 the apex of the posterior tibiae serrated within. 



Note. The generic characters are given at length in conse- 



