LAMB— DIPTERA : LONCH^ID^, SAPROMYZID^, EPHYDRID^, ETC. 343 



Abdomen. Black, sometimes a little paler at the base. $ with a shoi-t fine ovi- 

 positor. 



Size about 2 mm. 



Localities. Seychelles. Silhouette: highest forest, 2000 ft.; near Mont Pot-a-eau, about 

 1500 ft., VIII. 1908; Mare aux Cochons and forest above, IX. 1908. Mahe: high forest 

 of Morne Blanc and Pilot, X.— XL 1908: Mare aux Cochons district, 1500—2000 ft., 

 L— II. 1909; Cascade Estate, about 1000 ft., 1908—9. 



50. Oscinis halterata, n. sp. 



This species is similar in form of venation to 0. longipennis: it is also entirely 

 shining black. 



Head (PI. 16, figs. 16, 17). Somewhat as 0. oculata but the jowls are just visible 

 in profile; they are grey in colour. The antennae are not deep black, but very dark 

 brownish or reddish black, and reddish on the inner faces. 



Thorax. Scutellum and wings as in 0. longipennis, but the cross veins are nearer 

 together and the wings are slightly shorter. 



Halters black. 



Legs yellow with all the femora and the middle and hind tibiae slightly darkened. 



Abdomen. Shorter and dark haired. $ with a long ovipositor. 

 Size about l-j mm. - ' 



Localities. Seychelles. Mahe: marshes on coastal plain, Anse aux Pins and Anse 

 Royale, I. 1909; Anonyme Island, I. 1909. 



51. Oscinis varicornis, n. sp. 



Two specimens can be referred to another species. In the characters of thorax, wings, 

 legs and abdomen it is like 0. longipemiis except that the wings are slightly shorter 

 in proportion and the halters are infuscate and not clear yellow. The chief differences 

 are in the head. 



Head (PI. 16, fig. 18). Side view as figured, well marked jowls being present and 

 the mouth margin slightly projecting. The frontal triangle is much as in 0. longipennis, 

 the eye-margins black and shiny ; the facial pit is less deep and slightly wider. 



The third joint of the antennae is red on the lower half and black on the upper, the 

 arista is perceptibly pale at the extreme base. 



In other re.spects the insect is very like 0. longipennis, but the legs are clear 

 orange yellow. 



Size. 2\ mm. 



Localities. Seychelles. Mahe: country above Port Glaud, 500 — 800 ft., 5. XL 1908; 

 marshes on coastal plain, Anse aux Pins and Anse Royale, L 1909. 



SECOND SERIES— ZOOLOGY, VOL. XV. 44 



