in the Collection of W. W. Saunders, Esq. 203 



about four times the length of the second ; arista black, plumose ; 

 thorax with hoary tomentum ; pectus and scutellum dull testa- 

 ceous ; abdomen testaceous, a little longer and more slender than 

 the thorax ; tip black, with white tomentum ; legs black, slender, 

 very long ; femora, except the tips, knees and coxae, testaceous ; 

 wings grey, slightly brownish along the costa : veins black, 

 testaceous towards the base ; praebrachial vein forming an ex- 

 tremely obtuse angle at its flexure, from whence it is very 

 slightly curved to its tip, which ends at very little in front of the 

 tip of the wing ; discal transverse vein much curved inward near 

 its base, very slightly curved outward from thence to its tip, 

 parted by much less than its length from the border, and by a 

 little more than its length from the flexure of the praebrachial ; 

 alulae with a slight testaceous tinge. 



Length of the body 4 lines ; of the wings 7 lines. 



Valley of the Amazon. 



Dexia extrema. 



Mas, — Nigra, subaurata, capite pectoreque albidis, palpis an- 

 tennisque testaceis, abdomine testaceo, apice nigro nitente, 

 pedibus sat longis, coxis femoribusque testaceis, alis cinereis, 

 basi costaque subtestaceis, costae apice venisque fusco- 

 nebulosis, venis testaceis apice nigris, alulis albidis testaceo- 

 niarginatis. 



Male. — Black, with slightly gilded tomentum and a few black 

 bristles ; head whitish in front and beneath ; facialia without 

 bristles ; epistoma not prominent ; eyes bare ; palpi testaceous ; 

 antennae testaceous ; third joint full twice the length of the second, 

 not extending beyond half the length of the face ; pectus whitish ; 

 abdomen testaceous, elongate-obconical, much longer than the 

 thorax, black and shining and with a few black spines at the tip ; 

 legs slender, moderately long ; coxae and femora testaceous ; wings 

 grey, with a slight testaceous tinge at the base and along part of 

 the costa, clouded with brown towards the tip of the costa and 

 along the veins ; veins testaceous, black towards the tips ; prae- 

 brachial vein forming a rounded and extremely oblique angle at 

 its flexure, straight from thence to its tip, which ends at some 

 little distance in front of the tip of the wing ; discal transverse 

 vein straight, parted by little more than half its length from the 

 border and by rather less than its length from the flexure of the 

 praebrachial ; alulae whitish, with broad testaceous borders. 



Length of the body 4^ lines ; of the wings 8 lines. 



Valley of the Amazon. 



