INTRODUCTION. 4 1 



12. Rhamphidia flavipes Macq. is described below under this 

 name. 



13. Limnobia gracilis Wied. is either a Limnophila or an 

 Amalopis, distinguished by its large size (1 lines) and its abdo- 

 men being much longer than the wings. The description of this 

 species is reproduced in the Appendix to this volume. 



14. Limnobia humeralis Say; a Limnophila. I would in- 

 cline to the opinion of Wiedemann and consider this species 

 as synonymous with L. lenuipes Say, if in a copy of Wiedemann's 

 work at the Academy of Natural Sciences in Philadelphia I had 

 not found a marginal note, in Say's handwriting, positively deny- 

 ing this synonymy. Say describes only a female ; the venation 

 is the same as that of tenuipes, and altogether the resemblance 

 of the two species must be very great. I reproduce the descrip- 

 tion of L. humeralis in the Appendix. 



15. Limnobia ignobilis Walk. (Dipt. Saund.) has the venation 

 like Meigen, Tab. YI, fig. 5, that is, a single submarginal cell ; 

 there is a stump of a vein near the origin of the prsefurca. I 

 know of no such species. The description will be reproduced 

 in the Appendix to this volume. 



16. Limnobia macrocera Say = Limnophila macrocera (comp. 

 below). 



17. Limnobia prominens Walk, is very probably Rhamphidia 

 flavipes Macq. 



18. Limnobia rivosa of Fabricius' Fauna Grcenlandica is 

 probably Pedicia albivitta, which is indeed very like the European 

 Pedicia rivosa. 



19. Limnobia rostrata Say = Geranomyia rostrata (comp. 

 below). 



20. Limnobia simulans Walk. = Dicranomyia defuncta 0. S. 

 I have seen the original at the British Museum, an old and faded 

 specimen. Mr. Walker describes the species as "pale yellow, 

 legs yellow, tips of thighs, of the shanks and of the feet black ;" 

 whereas, in reality, the body is blackish, the legs are dark brown, 

 almost black, with a white band before the tip, etc. 



21. Limnobia tenuipes Say = Limnophila tenuipes (comp. 

 below). 



22. Limnobia turpis Walk. (Dipt. Saund.). Yenation like 

 Meig. Tab. Y, fig. 5, that is, a single submarginal cell and five 

 posterior cells. All the known Limnobiae with a single sub- 



