364 Proceedings of the Royal Irish Academy. 



N'cwicula palpelrcdis, (DeBreb.) ^^laiine. 



Yalye broadly elliptical, lanceolate at the ends ; striae distinctly 

 costate, linear, radiate, marginal ; intermediate free space "svide, ellip- 

 tical-lanceolate ; length -0034, breadth -0013. (PL 31, fig. 20.) 



^\m. Sm., B. D., Tol. i., p. 50. Supp., PL xxxi., fig. 273. The 

 figure represents the striae as minutely punctate ; in reality they are 

 strongly costate. Ptalfs, in Pritch., p. 905. Grunow, Yerhand. der 

 K. K. Zool. Bot. GeseU., Band s., 160, p. 536, T. iii., fig. 27. The 

 form here described exactly resembles that of Smith, being very small, 

 and with minutely punctate striae. Donkin, jST. H. Biit. Diat., p. 25, 

 fig. 3. This author regards the species as identical with Xavicula 

 barclayana, Greg. Eab. PL Eur. Alg., sect, i., p. 182, who describes 

 the striae as distinctly gi'anulate. 



Stomachs of Ascidians, Broadhaven Bay, Arran Islands, Co. Gal- 

 way. 



Navicula angulosa, (Greg.) Marine. 



Similar to the preceding, but striae finer and closer, and longer, 

 conYergent in the middle, radiate towards the ends ; intermediate 

 free space, instead of being elliptical, is lanceolate ; length -0050, 

 breadth -0010. 



Gregoiy, Q. J. M. S., 1856, p. 42, PL v., fig. 8. Ealfs, in Pritch., 

 p. 905. Eab. PL Eui\ Alg., sect, i., p. 176. Donkin, IS". H. Brit. 

 Diat., p. 26, PI. iy., fig. 4. 



Eiver Slaney, Eallurin, Tacumshane, Co. "Wexford. Breaches, 

 near jSTewcastle, Co. Wicklow. Malahide, Co. Dublin. Ai-ran Islands, 

 Co. Galway. 



Nafcicula semiplena, (Gregory). Marine. 



Yalye as in the preceding form, but much narrower, and the in- 

 termediate free space not angular in the middle. 



Donkin, X. H. Brit. Diat., p. 26, PL iy., fig. 5. — Pinnularia an- 

 gulosa, yar. ^_, Gregory, Q. J. M. S., 1856, p. 42, PL y.. fig. 8-^'— 

 Pinnularia semiplena, Greville, Q. J. M. S., 1859, p. 84, PL yi., fig. 12. 



Malahide, Co. Dublin. Fintragh Bay, Co. Donegal. Eostreyor, 

 Co. Down. 



Navicida hehes, (Ealfs). Fresh water. 



Yalye gibbous in the middle, ends somewhat attenuated, but 

 still broad, and rounded. Stride fine, linear, nearly parallel ; interme- 

 diate free space wide in middle, lanceolate towards the ends. (PL 

 31, fig. 21.) 



Ealfs, in Pritch., p. 896, who regards the species as identical with 

 Navicula obtusa, Wm. Sm., B. D., Yol. i., p. 50, PL xvi., fig. 140, 

 with which I find it impossible to identify it. Donkin, X. H. Brit., 

 Diat., p, 23, PL iii., fig. 12. 



Marl, Co. Down. Lough Mourne deposit. 



