AUSTRO-MALAYAN DIPTERA 477 



US to recognize that, in its generic characters, A. oculaius coin- 

 cides, not with the above-mentioned two species, but with the 

 species collected by M.'' Wallace in New Guinea and the adja- 

 cent islands. The large tegulae and the square distal end of 

 the anal cell, taken in connection with the general habitus and 

 coloring of A. oculatus render this conclusion certain, and even 

 lead me to suppose , as I will show belov^, that A. oculatus 

 may be identical with one of M.'^ Wallace's species. The state- 

 ment in Wiedemann's essay (p. 1 3), that the arista is glabrous, 

 is erroneous, and without any foundation, because Latreilk in 

 his communication about the type of Fabricius explicitly says 

 that the arista is broken off (p. 14). 



The species of Achias were found, as M.'' D'Albertis told me, 

 on human alvine dejections. 



While at work in the Brit. Mus. in July 1880, I drew up for 

 my own use the following tabular arrangement of the species 

 which may be considered as belonging to Achias^, in the sense 

 of Wiedemann. Imperfect and hastily put together as it is , it 

 may be of some use to others ; I have added my own A. Al- 

 hertisii to it, which^ after a good deal of hesitation, 1 concluded 

 to consider as distinct from A. longividens. 



Costa not darker colored — venusfcula Walk. J. Pr. Ian. Soc VIII , 119 (New 



Guinea). 

 Costa darker colored 



Femora yellow. 



Stout species — amplividens Walk. 1. c. Ill, 122 (Aru Isl-ds) and 



Westwood, Tr. Ent. Soc N. S. V. 

 Tab. 13, f. 7. 

 brachyophthalina Walk. 1. c. VIII . 119 (New 

 Guinea). 



Narrow, elongated species — dacoides Walk. 1. c- VIII . 133 (Sal- 



watti) ?. 

 (Syn. «" aspiciens Wk. 1- c VII, 229 =.'. 

 Waigiou). 



Femora broadly black at tip — longividens Walk. 1. c III, 121 (Aru) and 



Westwood, 1. c. 



lativi dens Walk. 1. c. Ill, 121 (Aru) and 

 Westwood, 1. c 



Albertisi n. sp. (N. Guinea). 



