176 DIPTEEA. 



visible, although they are rather extensive, nearly filling the discal cell and the discal 

 ends of the anal and axillary cells ; the abdomen is not at all coarctate, but gently 

 tapering towards the tip. 



5. Diogmites tan, sp. n., $ . (Tab. III. fig. 11.) 



Thoracic stripes deep black, coalescent, the anterior end of the intermediate one expanded into a distinct 



knob ; the shadows on the distal half of the wings rather dark. 

 Length 23-24 millim. 



Hal. Panama, Volcan de Chiriqui 3000 to 4000 feet (Champion). 



Head orichalceo-pollinose ; mystax whitish ; palpi brown, with black hairs ; antennee 

 rufous. Thoracic dorsum with a golden-pollinose border all round (in front of the 

 scutellum this golden border shows an expansion, which is emarginate in the middle 

 and fills out the space between the posterior ends of the lateral thoracic stripes) ; the 

 disc deep velvety-black, the three usual stripes coalescing completely (the anterior end 

 of the middle stripe, in front of the collar, expanding into a stout deep black knob, 

 slightly brownish anteriorly ; on each side of the middle stripe is an orichalceo-pollinose 

 excision between this knob and the anterior end of the lateral stripes) ; a slight yellow 

 margin along the transverse thoracic suture. Abdomen very slightly coarctate ; of a 

 rich reddish-brown, somewhat lighter along the posterior margins of the segments ; the 

 surface beset with moderately dense, short, appressed reddish hairs. Halteres brownish. 

 Front coxae orichalceo-pollinose, with sparse long yellow hair. Legs brownish-rufous, 

 the tarsi black; metatarsi and, on the four anterior legs, the second joint more or less 

 dark rufous ; the usual short rufous pile on the inner sides of the front and hind tibiae 

 and on the metatarsi quite conspicuous. Wings subhyaline, with an almost imper- 

 ceptible yellowish tinge ; the usual shadows brownish-grey, quite conspicuous, and 

 filling the distal end of the marginal, the distal half of the first submarginal, the whole 

 of the second submarginal, the distal half of the first posterior, and the whole of 

 the second and third posterior cells ; the discal cell contains a large, and the fourth 

 posterior cell a smaller, grey triangle, and the fifth cell a small shadow ; the anal and 

 axillary cells are subhyaline, without shadow. — A single female. 



D. goniostigma, Bellardi (Saggio &c. ii. p. 65, t. 1. f. 6), from Mexico, has a thorax 

 somewhat resembling that of D. tau ; it is, however, much smaller, and also differs in 

 other respects. 



6. Diogmites rubescens. 



Dasypogon (Saropogon) rubescens, Bellardi, Saggio &c. ii. p. 71 \ 



Hah. Mexico (de Saussure x ), Tuxpango (Sumichrast *), Orizaba. 



To Prof. Bellardi's description I would add that the ocellar bristles are very short, and 

 that the hind femora have, on the antero-superior side, a brown stripe, which is more or 

 less distinct in different specimens, sometimes evanescent ; the tips of the femora and 

 the distal third of the tibia? are also more or less dark. The abdomen is very slightly 



