360 Proceedings of the Royal Irish Acadenvy. 
and the only three localities in which I have found it in Ireland, if 
not marine, are certainly brackish. 
Kitz. Bac., p. 94, T. i1., fig. 55, who attributes the species to 
Ehrenberg. Ralfs, in Pritch., p. 901, who regards it as distinct from 
Navicula sculpta, Ehr. Grunow, Verhand. der K. K. Zool. Bot. 
Gesell., Band x., 1860, p. 540, who states that he did not find the 
form in the Santa Fiore Bergmehl. examined by him, but confirms 
Donkin’s statement of having obtained it in the Franzensbad deposit. 
Donkin, N. H. Brit., Diat., p. 15, Pl. i., fig. 9. Rab. Fl. Mur, Ale, 
sect. 1., p. 197. 
Seashore, Queenstown, Co. Cork. Breaches, Co. Wicklow. Salt 
Hill, Co. Dublin. 
Navicula tenuirostris, N.S. Marine. . 
Valve elliptical, with long produced narrow apices; length :0018, 
breadth :0006; striz fine, parallel in the middle, and slightly radiate 
towards the ends; less distinct midway between the margin and the 
longitudinal sulcus; intermediate free space narrow, apparently ex- 
panding in the middle in a short and very narrow stauroform band. 
(Plate 31, fig. 9.) 
Stomachs of Ascidians, Broadhaven Bay, Co. Galway. 
Vavicula ambigua, (Ehr.) Fresh water. 
Valves elliptical, ends produced and capitate; length +0032, 
breadth :0010; strie fine, parallel. (Plate 31, fig. 10.) 
Kitz. Bac., p. 95, T. xxvii., fig. 66, who attributes the species to 
Ehrenberg. Wm. Sm., B.D., Vol.i., p. 51, Pl. xvi., fig. 149. Rab. 
Siissw. Diat., p. 40, T. vi., fig. 59.  Ralfs, in Pritch., p. 902. Gru- 
now, Verhand. der K. K. Zool. Bot. Gesell., Band x., 1860, p. 529, T. 
iv., fig. 33. Cleve, Om Svenska och Norska Diat., p. 228. Donkin, 
N.:8., But. Diat., p..39,. Pl. vi,, ig. co: 
River Erne, near Crossdoney, Co. Cavan. Pool near Glencar, Co. 
Cork. River Bann, near Coleraine, Co. Londonderry. 
Navicula spherophora, (Kiitz.) Fresh water. 
Valve elliptical; ends considerably produced and capitate; stric 
fine, punctate, slightly convergent; length ‘0030, breadth ‘0010. 
(Plate 31; fig. 11.) 
Kutz. Bac., p.95,;di9, ue: Lf... Wie ema, 1. Viola: woe 
Pl. xvui., fig. 148, who represents the strie as moniliform, an appear- 
ance they present only when not in focus. Rab. Siissw. Diat., p. 40, 
T. vi., fig. 65a, 65b being, as it would appear, a very distinct form. 
Ralfs, in Pritch., p. 899. Grunow, Verhand. der K. K. Zool. Bot. 
