O’Mrari—Report on the Irish Diatomacee. 301 
somewhat radiately arranged. They differ as respects the character 
of the striation. In Synedra barbatula the strive are easily detected, 
and are divided by a narrow, longitudinal sulcus; in the smaller spe- 
cimens of Synedra gracilis the striation is obscure, but in the larger 
forms the striz are apparent and pervious. 
From stomachs of Ascidians, Roundstone Bay, Co. Galway. From 
seaweeds, Drehidnamaud, Co. Kerry. Seaweeds, Salthill, Co. Dub- 
lin. Seaweeds, Tramore, Co. Waterford. Seaweeds, Greenore, Co. 
Louth. 
(b.) Lrustules arcuate on side view, stri@ pervious. 
Synedra undulata, (Bail.) Marine. 
Frustules very long and narrow, with undulate margins ; expanded 
im the middle and towards the ends; strie moniliform. (Pl. 28, 
fig. 14.) 
Gregory, Diat. of Clyde, p. 59, PI. xiv., fig. 107. Wm. Sm., B.D., 
Vol. u., p. 97. Ralfs, in Pritch., p. 786. Grunow, Verhand. der K.K. 
Zool. Bot. Gesel., Band xu., p. 405, T. vi., fig. 1. Cleve,Om Svenska 
och Norska Diat., p. 220. Rab. Fl. Eur., sect. 1, p. 130.—Toxarium 
undulatum, Bailey, Mic. Obs., p. 15, figs. 24, 25. 
Grunow associates this species with forms characterised by the 
fact of the strie being interrupted in the middle, and it is so repre- 
sented in the figure above referred to; but I have ever found the 
strlz pervious, as in Gregory’s figure. 
Stomachs of Ascidians, Co. Clare, Stomachs of Ascidians, Round- 
stone Bay, Co. Galway. Stomachs of Ascidians, and also from sea- 
weeds, in great abundance, Belfast Lough, Co. Antrim. 
Synedra lunaris, (Ehr.) Fresh water. 
Frustules on front view quadrangular; on side view arcuate, at- 
tenuated tewards the extremities; striz linear, fine, but distinct; stipes 
short. . (Pl. 28, fig. 15.) 
Ebr. ‘Infus., .'T. xviui:, fig: 4. Kutz. Bac. p. 65,.T..11., fig. 11. 
War Su, B. Ds, Volyi.5.p..69;/P i). x1.,/fig. 82. Rab. .Stissw. -Diat., 
p. 54, T. v., fig. 6. Ralfs, in Pritch., p. 185. Grunow, Verhand. der 
K. K. Zool. Bot. Gesel., Band xii., 1862, p. 389. Heiberg, De Danske 
Diat., p. 65. Rab. Fl. Eur., sect. 1, p. 128. Cleve, Om Svenska och 
Norska Diat., p. 220. Castracane, Catalogo di Diat. raccolte nell Val 
Intrasea, p. 10. 
Lucan, Co. Dublin. Glenchree, Glenmalure, Co. Wicklow. 
Derrylane Lough, Co. Cavan. Bellarena, Co. Londonderry. Five- 
niletown, Lisnaskea, Co. Fermanagh. Pool, Glencar, Drumoughty 
Lough, near Kenmare, Co. Kerry. Bantry, Co. Cork. Connemara, 
Co. Galway. 
202 
