O'Meara — Report on the Irish Diatomacecc. 317 



Pritch., p. 810, PI. iv., fig. 51, 52.Grunow, Ycrhaud. der K. K. ZooL 

 Bot. Gesel., Bandxii., 1862, p. 319. Eab. PI. Eur., sect. 1, p. 300. 



Lough Derg, Co. Galway. Ulster Caual, near Newry, Co. Armagh. 

 Only a few forms were found in these localities, the species being one 

 of the rarest in Ireland. 



Genus II. T.^lBellabia, Ehr. 



Prustules attached in zig-zag filaments ; valves expanded at the 

 middle and ends ; strise faint. 



TabeUaria flocculosa, (Poth.) Presh water. 



Diaphragms numerous, thickened ends alternately placed, and 

 varying in length. (PL 29, fig. 3.) 



Kiitz. Bac, p. 127, T. xvii., fig. 21. Rab. Sussw. Diat., p. 63, 

 T. X., fig. 2. Wm. Sm. B. D., Vol. ii., p. 45, PI. xliii., fig. 316. 

 Palfs, in Pritch., p. 807, PL xiii., fig. 29. Grunow, Verhand. der K. 

 K. ZooL Bot. Gesel., Band xii., 1862, p. 410. Heiberg, De Danskc 

 Diat., p. 70. Castracane, Catalogo di Diat. raccolte nell Val Intrasca, 

 p. 15. Cleve, Om Svenska och Norska Diat., p. 221. — TabeUaria 

 ventricosa, Kiitz. Bac, p. 127, T. xxx., fig. 74, does not differ from 

 the present species. 



Prequent, especially in sub-Alpine and boggy pools. Kiitzing re- 

 gards this species as identical with Conferva flocculosa, Eoth., on which 

 authority the species is attributed to Both. 



TabeUaria fenestrata, (Lyngb.) Presh water. 



Diaphragms few, and of equal thickness on both sides of the cen- 

 tral expansion ; frustules much longer than in the preceding species. 



Kutz. Bac, p. 127, T. xvii., fig. 22, T. xviii., fig. 2, and T. xxx., 

 fig. 73, who regards the species as identical with Diatoma fenestratum 

 Lyngbye. Pab. Siissw. Diat., p. 63, T. x., fig. 1. "Wm. Sm., B. D., 

 Vol. ii., p. 46, PL xlviii., fig. 317. Palfs, in Pritch, p. 807. Grunow, 

 Verhand. der K.K. ZooL Bot. Gesel., Band xii., 1862, p. 410. Heiberg, 

 DeDanske Diat., p. 71. Castracane Catalogo di Diat. raccolte nell Val 

 Intrasca, p. 16. Cleve, Om Svenska och IS^orska Diat., p. 321. 



Common in the same localities as the preceding, with which it is 

 usually mixed. 



Genus III. Teteacyclits, Ralfs. 



Prustules united in parallel filaments ; filaments free ; thickened 



2 P2 



