310 Proceedings of the Royal Irish Academy. 



Synedra salina, {Wm.. Sm.) Marine. 



Yalve lanceolate, gradually attenuated towards the ends, which are 

 rounded off, and broader than in Sjnedi'a splendens. (PI. 28, fig. 32.) 



Wm. Sm., B. D., Vol. i., p. 71, PL xi., fig. 88. Ralfs, in Pritch., 

 p. 787. Grunow, Verhand. der K. K. Zool. Bot. Gesel. Band xii. 

 p. 398. — Synedra ulna, var. marina Hab. Fl . Eur., sect. 1, p. 134. 



Tacumshane, Co. "Wexford. Malahide, Clontarf, Co. Dublin. Eos- 

 treTor, Co. Down. Stomachs of Ascidians, E-oundstone Bay, Co. Galway. 



Synedra yallionii, (Ehr.) Marine. 



Erustules on front view slightly attenuated at the ends, on side 

 view shorter, broader, and more obtuse at ends than in case of Synedra 

 «alina. (PI. 28, fig. 33.) 



Kiitz. Bac, p. 68, T. xxx., fig. 42. ^'m. Sm., B. D., Yol. i., p. 

 74. Supp. PI. XXX., fig. 265, who describes a shorter and stouter 

 Tar. ih., Supp. PL xxx., fig. 265 B. Ealfs, in Pritch, p. 788, PL 

 xii., figs. 34-36. Grunow, Yerhand der K. K., Zool. Bot. Gesel., 

 Band xii., 1862, p. 401. Eab. Fl. Eur., sect. 1, p. 137, who attributes 

 the species to Bory. 



On seaweeds, Bannow, and Tacumshane, Co. Wexford. On sea- 

 weeds, Malahide, Co. Dublin. Seaweeds, Larne, Co. Antrim. Sea- 

 weeds, Dundrum Bay, Co. Down. Arran Islands, Co. Galway, and 

 from seaweeds at different parts of the coast in the Co. Clare. 



The smaller variety has been found at Malahide, Howth, Co. 

 Dublin. On seaweeds, Larne, Co. Antrim, and in the other localities 

 where the larger species has occurred. 



Synedra spathulata, I^. S. Fresh water. 



Frustules very large ; length, -0130 ; on front view wider at ends 

 Ihan middle; greatest breadth, "0012; ends straight; on side view 

 wider in the middle, and gradually attenuated towards the ends, at 

 some distance from which -0028, bending inwards and then outwards, 

 then suddenly constricted towards the broadly capitate rounded extre- 

 mities. Striae course, costate. (PL 28, fig. 34.) 



Ditch at bank of Eoyal Canal, near Kilcock, Co. Kildare. An un- 

 dulate variety of the species occurs in a well, I^ewcastle, Lyons, Co. 

 Dublin. 



Synedra larlatula, (Kiitz.) Marine. 



Frustules short, on fi-ont view quadi-angular ; on side view broadly 

 elliptical ; striae fine, but distinct. (PL 28, fig. 35.) 



Kutz. Bac, p. 68, T. xv., fig. 104. Ealfs, in Pritch., p. 789.— 

 Synedi'a gracilis, var. barbatula, Grunow, Yerhand. der K.K. Zool. Bot., 

 Gesel., Band xii., p. 402. 



Salthill, Co. Dublin. Stomachs of Ascidians, Eoundstone Bay, 

 €0. Galway. Seaweeds, Tramore, Co. "Waterford. 



