322 



PERCY SLADEN TRUST EXPEDITION 



Abdomen black and shining, otherwise hke that of /. sinlota. 

 Size. \\ mm. 



Locality. Seychelles. Mah^ : from marshy ground near sea-level at Cascade, 20. 

 II. 1909. 



23. llythea invenata, n. sp. 



This species is very close to the last as regards its main characters. The characters 

 of head, thorax, etc. are practically the same, the principal difference being the reddish 

 colour of the facial dusting, the longer scutellar bristles, the more orange-yellow legs with 

 the front coxae nearly black. 



Wings (Fig. 12). These offer a very striking peculiarity inasmuch as the cross veins 

 are absent : the picture on the wings is more like that of the typical species. 



Four specimens of this new species are in the Cambridge Collection and were sent by 

 Mr F. Muir from Durban. 



Size about 1^ mm. 



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

 Eoyale, I. 1909. 



Fig. 12. llythea invenata, n. sp., wing. 



Fig. 1 3. Psilopa nitidissima, n. sp., wing. 



PsiLOPA, Fallen. 



Psilopa Fallen, Dipt. Suae, Hydromyz., (1823), p. 7. 



24. Psilopa nitidissima, n. sp. 



This species is very closely related to the Palaearctic species P. compta Meigen ; 

 it is however much more shining, being brilliant green with coppery or ]3urplish reflections 

 instead of pure green. In the description given comparison is made with P. compta. 



Head similar in form, chaetotaxy etc. including the antennge, except for being 

 brilliantly shining. 



Thorax. Similar ; scutellum more swollen at the sides, the flattened part of disc 

 smaller, and the whole somewhat smaller in proportion and more rounded in outline. 



Wings (Fig. 13) difier in that the second vein is shorter. 



Legs ; differ in that the tibiae are all blackened in the middle. 



Abdomen, very shining, the distal part is red-coppery in colour. 



Size. 2 mm. 



Locality. Seychelles. Mahd : from marshes on coastal plain, Anse aux Pins and 

 Anse Royale, I. 1909. 



