MESOSTENUS. 225 



the tubercle below them, the greater part of the mesopleura, a mark below the hind 

 wings, the greater part of the metapleura (forming a large oval mark), a broad line on 

 the edge of the pronotum, two longish marks on the mesonotum, the scutellum, a some- 

 what lunate mark on either side of the metanotum, and a longish mark between them, 

 and two longish somewhat oval marks on the apex of the metanotum, yellow. First 

 abdominal segment black, the apex yellow ; second with the apex broadly yellow ; third 

 yellow, with two oblique marks and the base and the apex, black ; fourth black, the 

 apex yellow ; the rest yellow, as is also the ventral surface. Legs yellow ; the base 

 and apex of the four posterior trochanters, a mark on the lower side of the hind coxae 

 at the base, and a larger and longer mark on the outer side, the femora above, and the 

 apices of the hind tibiae broadly, black. Areolet longish, widest at the base, angled 

 where the recurrent nervure is received, the apical nervure faint, 



31. Mesostenus COStaricensis. (Mesostenus nicaraguensis, Tab. X. fig. 13.) 



Niger, flavo-varius ; apice scutelli, pleuris sternoque flavis ; pedibus flans, femoribus supra nigris ; alis 



hyalinis. $ . 

 Long. 13 millim. ; terebra 5 millim. 



Hab. Costa Rica, Irazu 6000 to 7000 feet (Rogers). 



Antennae stout, longer than the body, the yellow ring on the flagellum not very broad. 

 Head yellow, except behind ; the centre of the vertex and the mandibles punctured. 

 Thorax strongly punctured ; the tegulae, the tubercle beneath them, the edge of the 

 pronotum, the mesopleura (except the suture and immediately beneath the wings), two 

 lines on the mesonotum, the scutellar carinae, the apical half of the scutellum, the post- 

 scutellum, two large marks on the apex of the metanotum (covering and extending above 

 the spines), and the greater part of the metapleura, yellow. Scutellum impunctate. 

 Base of the metanotum almost impunctate, the apex transversely, the sides longitudinally, 

 striated ; spines stout, curved. First abdominal segment yellow, a large black band at 

 the apex of the petiole ; second and third segments black, yellow at the apex ; fourth 

 segment yellow, black at the base ; the other segments yellow. The anterior coxae 

 have a small black mark at the side, and the hind coxae have a large black line ; the 

 trochanters in part, and the femora above, black. Areolet narrow, longer than broad. 



32. Mesostenus longipes. 



Niger, flavo-varius ; pleuris, sterno scutelloque, flavis ; pedibus flavis, anterioribus femoribus tibiisque posticis 



supra, nigro-lineatis. 

 Long. 13 millim. 



Hab. Costa Rica, Cache (Rogers). 



Antennae stout, the yellow ring on the flagellum interrupted on the lower side. 

 Head punctured, yellow behind, the middle of the vertex and the mandibles black. 

 Thorax coarsely punctured, reticulated in the centre of the mesonotum and pleurae ; 



biol. centr.-amer., Hymenopt., November 1885. 2 gg 



