304 Proceedings of the Royal Irish Academy. 



Ereaches, near I'I'ewcastle. On moist rock, Black Castle, Co. "W^ick- 

 \o\r. Tacumshane, Co. "Wexford. 



Var. acicularis, (TVm. Sm.) Fresli water. 



EesemlDling Synedra pulcliella, only longer and narrower. (PL 

 28, fig. 19.) 



Wm. Sm., B. D., Yol. i., p. 70, PL xi., fig. 86, wLo regards it as 

 a brackish, water form. — Synedra l^vis, Kiitz. Bac, p. 65, T. xy., 

 fig. 8. 2. 3. 4. "Were this the case, the variety should be attributed 

 to Kiitzing, and be called var. Isevis ; but Kiitzing's figxire is not 

 sufficiently distinct to enable me to identify the variety with it, and 

 therefore I deem it better to retain the name given by Smith, who 

 figures it with accui^acy. — Synedra Smithii, Palfs, in Pritch., p. 786.. 

 Grunow, Yerhand. der Zool. Bot. GeseL, Band xii., 1862, p. 392, who 

 remarks, "that it is probably only a veiy long variety of (what he 

 calls) Synedra fasciculata, mixed up with which he found it upon 

 Cladophora flavida, Kiitz., on tbe Peene at Woolgart, and in such 

 manner that no clear distinction existed between the two." Bab. Fl^ 

 Eur., sect. 1, p. 131. 



Eiver Slaney, Eallurin, Co. "Wexford. Lough Gill, Co. Kerry.. 

 Carrickhugh, Co. Deny. Kilcool, moist rock. Black Castle, Co. 

 • "Wicklow. In the last named locality, in which this form was found- 

 abundantly, marine influence was scarcely possible. 



Var. lanceolata, (Wm. Sm.) Fresli water. 



Kesembling the typical form, but shorter and broader in proportion., 

 (PL 28, fig. 20.) 



Synedra minutissima, "Wm. Sm., B. D., Yol. i., p. 70, PL xi., 

 fig. 87, who ascribes the species to Kiitzing, but the form so called by 

 the last named author, Bac, p. 63, T. iii., fig. 30, can scarcely be 

 identical with it. More likely it is the same as that which Kiitzing 

 describes as Synedi^a lanceolata : but whether or not this be the case, 

 the designation is adopted because of its appropriateness, and the 

 species attributed to "Wm. Smith, whose figiire admits of no mistake. 

 Ealfs, in Pritch., p. 786. Heiberg, De Danske Diat., p. 65, who^ 

 attributes the form to fi'esh or brackish water. Bab. PL Eur., sect. 

 1, p. 139. — Synedra vaucherife, Grunow, who adopts this view with, 

 doubtfulness, Yerhand. der K. K. Zool. Bot. GeseL, Band xii., 1862, 

 p. 393, T. v., fig. 9. This last named author regards Synedra vaucheriae,, 

 Kiitz., as distinct from the form so named by Wm. Sm., and the 

 former identical with that figured as Synedra minutissima, by Wm.. 

 Smith. 



River Slaney, Killurin, Co. "Wexford. Eiver at Port-na-Crush, 

 and stream, Eintragh, Co. Donegal. Stream, Howth, Co. Dublin. 

 Stream near Giants' Causeway, Co. Antrim. Kilcool, Black Castle, 

 Co. "Wicklow. 



