a Family'^)/ the Hymenoptera Heterogyna. 201 



Sp. 5. Lab. Swaiiisonii, Shuck. Length 6^ lines ; 



^ Expansion 13 lines. 

 Rufo-testaceus, pnbesvens, capife {mandibiilis antennisque excepth) cas- 



taneo : pedunculo abdominis fransverso-quadrafo siqira subconvcvo ; 



pedibus brevis. 



Body of a pale reddish testaceous. Head, with the exception of the man- 

 dibles and antennae, of a bright castaneous ; the carina? of the face, 

 behind which the antennae are inserted, very prominent, and termi- 

 nating gradually in front of the anterior ocellus; the ocelli placed in a 

 curved line on the vertex : the antennae having the flagellum at the 

 base, as stout as the scape, which is a little less than one-fourth the 

 length of the organ : mandibles long and very slender, leaving a large 

 semicircular space between them and the clypeus. 



Thorax in front and scutellum very gibbous ; metathorax perpendicular and 

 slightly produced laterally: superior wings with their nervures and 

 stigma pale testaceous : the marginal cell lanceolate, slightly acumi- 

 nated beyond the second submarginal, the first of the latter narrow, 

 pentagonal, less than the second, from which it is separated by a waved 

 nervure : the second also narrow, but growing more so towards its apex, 

 where it is separated by a short straight nervure from the following ; it 

 is much less than the marginal cell, and has the recurrent nervure in- 

 serted about its middle, beyond which to the apex of this cell the cu- 

 bital nervure is considerably thickened: legs short and slender. 



Abdomen slightly shining, its peduncle transverse-quadrate, with the angles 

 • rounded, the surface plane, except towards its apex, where it has a slight 

 convex transverse ridge, and is as wide as the second segment, its 

 ventral portion slightly produced ; the base of all the segments very 

 slightly constricted, and the extreme apex of the terminal one consi- 

 derably compressed vertically, where it has a deep fissure : the male 

 sexual organ protruding beneath, in the form of a deeply and con- 

 cavely emai-ginated plate, the lateral processes of which form acutely 

 acuminated slightly upcurved spines. 



In \x\y own collection^ 



This insect was captured by Mr. Sv^^ainson in the Brazils, to 

 whose entomological exertions there we are indebted for the know- 

 ledge of several undescribed species, and this I accordingly dedicate 

 to him. It is distinguished from the preceding by many particulars, 

 but most obviously by the relative proportions of the marginal and 

 first and second submarginal cells. *^-. 



[To be continued.] ; * Z. -^ ^^ 



Ann.NatJIi^. Vol.5. No. 30. May l%iO. 



