222 HYMENOPTEEA. 



blue, darker at the base ; the antennae with the flagellum fuscous-black. Head nearly 

 as wide as the thorax, distinctly retreating behind the eyes, sparsely covered with 

 blackish hair; the clypeus convex, the apex arcuate, but not quite rounded in the 

 middle ; the labrum finely punctured ; the palpi with the apices of the joints testaceous ; 

 the front above the antennae depressed, and with a deep channel in the centre. Thorax 

 velvety, opaque ; the pleurae distinctly tuberculate ; the median segment transversely 

 striated, but not strongly, the apex denticulate. Abdomen elongate; the apex densely 

 covered with black hairs. Legs bluish or violaceous. Wings deep, very brilliant 

 violet. 



Specimens of what I take to be the male have the antennae brownish at the apex ; 

 they have two dense tufts of stiff hairs on the fifth ventral segment and a small tuft on 

 the sixth segment. 



P. centralis may t be known from P. amabilis by the wings being of a brilliant 

 violaceous colour, without a trace of black or fuscous, and by the mesopleurae being 

 distinctly tuberculate. The male may be known by the dense tufts of hair on the fifth 

 ventral segment, these being absent in the corresponding sex of P. amabilis. 



V 



21. Pepsis obscura. 



Pepsis obscura, Lepel. de St.-Fargeau, Hist. Nat. des Ins. Hymen, iii. p. 490 \; Smith. Trans. Ent. 

 Soc. Lond. 3rd ser. i. p. 36 2 ; Cresson, Trans. Am. Ent. Soc. i. p. 149 3 . 



Hab. Panama 2 . — Brazil 1 . 



Smith 2 remarks that the insect from Panama " agrees precisely with the description, 

 excepting that the tips of the antennae are yellow, which is not mentioned by 

 St.-Fargeau ; still I am inclined to believe it is the same species, and probably the 

 male of P. elevata" 



Fam. SCOLIIMi. 



This well-marked family is not very numerously represented in our region ; but some 

 of its species are among the largest, most striking, and commonest of the Hymenoptera 

 inhabiting Central America. 



The family divides itself naturally into two sections — one, represented by Scolia and 

 Elis, large, often hairy species, with reniform eyes ; the other by Myzine and Tiphia, 

 which are much smaller and have not the eyes emarginate, except in the male of 

 Myzine. 



As regards Scolia and Mis, it may be remarked that they vary greatly in size, and 

 that the sculpture of the head and thorax is not always uniform in the same species, as 

 it becomes more or less altered through their burying habits. 



