368 Proceedings of ihe Royal Irkh Academy. 



Band x., 1860, p. 544, T. iii., fig. 28 : and likely also identical with 

 JSTavicnla limosa, var. bicameata, GrunoTV, Yerhand. der K. K. Zool. 

 Eot. Gesell., Band s., 1860, p. 545, T. v., fig, 7. 



Lougli Mask, near Tourmakeady, Co. ]Mayo. Kilcool, Co. "Wick- 

 low. Lough Gill, Co. Kerry. Pond in Botanical Gardens of Trinity 

 College, Dublin. 



Nmicula limosa , (Kiitz.) Presh water. 



Yalve triundulate on the margin, more expanded in the middle 

 than at the ends ; ends cuneate ; strife fine, parallel ; longitudinal free 

 space narrow, except in the middle, where it is slightly expanded ; 

 longitudinal strife easily observed, with good illumination; length 

 aboTit -0034, breadth in 'the middle -0006. (Plate 31, fig. 30.) 



Kiitz. Bac, p. 101, T. iii., fig. 50. Eab. Siissw. Diat., p. 41, T. 

 vi., fig. 31. Ealfs, in Pritch., p. 894, Grunow, Yerhand. der K. K. 

 Zool. Bot. Gesell., Band x., 1860, p. 544, T. t., fig. 86. Donkin, 

 Js^. H. Brit. Diat., p. 73, PL xii., fig. 61. Cleve, Cm Svenska och 

 j^orska Diat., p. 227. Lagerstedt, Soty. Diat. fi-an Spetsbergen och 

 Beeren Eiland, p. 30, T. i.,' fig. 6. 



Powerscouit, Co. Wicklow. Botanical Gardens of Tiinity College, 

 Dublin. 



Var. gihlenda, (Kiitz.) Fresh water. 



Like the typical species, differing only in this, that the ends instead 

 of being cuneate are rounded. 



Grunow, Yerhand. der K. K. Zool. Bot. Gesell., Band x., 1860, 

 p. 544, T. v., fig. 8a. Donkin, X. H. Brit. Diat., p. 73, PI. xii., fig. 6a. 

 — Xavicula gibbemla, Kiitz. Bac, p. 101, T. ui., fig. 50. "Wm. Sm., 

 B. D., Yol. i., p. 51, PL xviL, fig. 160. Schumann, Diat. der Hohen 

 Tatra, p. 76. Lagerstedt, Sotv. Diat. fi'an Spetsbergen och Beeren 

 Eiland, p. 38. 



River Erne, Crossdoney, Denylane Lough, Co. Cavan. Glengar- 

 riff, Co. Cork. Lough Neagh, near Lurgan, Co. Armagh. Streamlet 

 in Powerscourt demesne, Co. YTicklow. Lough bourne deposit. 



Var. iruncata, (Kiitz.) Fresh water. 



Yalve nearlv linear, with rounded ends ; the longitudinal sulci 

 waved; length -0025, breadth -00055. (Plate 31, fig. 31.) 



Grunow, Yerhand. der K. K. Zool. Bot. Gesell., Band x., 1860, 

 p. 545, T. v., figs. 8e and 9. — Xavicula truncata, Kiitz. Bac, p. 96, 

 T. iii., fig. 34, and T. v., fig. 4. Bab. Siissw. Diat., p. 39, T. vi., 

 fig. 67. 



Friarstown, Eiver Dodder, Co. Dublin. Lough Xeagh, near Lur- 

 gan, Co. Armagh. Lough Mask, near Tourmakeady, Co. Mayo. 

 Dundalk, Co. Louth. Wet rock, Ballyshannon, Co. l^onegal. Castle- 

 Gregory, Co. Keny. 



