222 Mr. A. H. Haliday on the generic distribution 



Subg. 1. NOTIPHILA. 



Nervus costalis in alse apice evanescens. Tibiae mediae extrorsum 

 spinosse. Facias perpendicularis lateribus ciliata. Palpi dilatati. 

 Abdomen depressum inerme. 



Sp. 1. cinerea, N : thorace ferruginoso, abdomine cinereo ni- 



gro-maculato, facie fulvescente, palpis tibiis tarsisque ferrugi- 



neis. 



Fallen Act. Holm. 1813. p. 250.— Hydrom. 8. Meig. Dipt. Eur. 



vi. 65. Macq. S. a B. ii. 521. pi. xxi. fig. 9. — Keratocera palustris, 



Desv. Myod. 88. — K. trapce 8{ fulvicornis, Ibid. 78. 9. 



Everywhere abundant in marshes. Desvoidy has observed 

 that it deposits its eggs in the flowers of Potamogeton, 



Sp. 2. riparia, N : thorace ferruginoso, abdomine cinereo nigro- 

 maculato, facie cinerea, palpis tibiis tarsisque ferrugineis, tibiis 

 annulo nigro. 



Meig. Dipt. Eur. vi. 65. Macq. S. aB. ii. 522. 



Found on the borders of the lake at Blarney Castle, county Cork. 



Sp. 3. w%?wo5a (Curtis App.), N: thorace ferruginoso, abdomine 

 cinereo nigro-maculato, facie fulvescente, palpis pedibus nigris, 

 tarsis ferrugineis ; m.f. 2 lin. 



In a marsh between GlengarifF and Adrighoule ; banks of the 

 Shannon at Tarbert ; shores of Belfast Lough, much less common 

 than the first species. 



Antennae and palpi black. Face tawny yellow. Frontals 

 dull black. Vertex, orbits, and thorax rusty brown. Abdo- 

 men cinereous, with a blackish spot at the sides of each seg- 

 ment. Legs black, the tarsi (at least the two hinder pair) 

 ferruginous. Halteres yellowish. Wings obscurely hyaline. 



Subg. 2. DiCH^TA, Meig. 



Abdomen maris convexum, apice bispinosum segmento penultimo 

 margine pectinate. Characteres reliqui fere quales Notiphilce. 



Sp. 4. caudata, N : D : nigra obscura, facie fulvescente, tarsis fer- 

 rugineis. 



Fallen Act. Holm. 1813. p. 249. Hydrom. 8. — Bichcdtaid. Meig. 

 Dipt. Eur. vi. 62. tab. bS. fig. 1—6. Macq. S. aB. ii. 521. pi. xxi. 

 fig. 8. 



Found in England. Communicated by F. Walker, Esq. 



Subg. 3. DiscoMYZA, Meig. 

 Aloe abdomen non superantes, postice decurvae. Tibiae mediae 



