354 Proceedings of the Royal Irish Academy. 



species as Pimiiilaria termes, Ehr. — Navicula mesolepta, var, nodulosa, 

 Gnmow, Yerhand. derK. K. Zool. Bot. Gesell., Band x., 1860, p. 320. 



Peatherbed Bog, Co. Dublin. Camolin, Co. Wexford. 



Navicula microstauron, (Ehr.) Eresb water. 



Yalve linear, oblong, attenuated towards tbe broadly rounded 

 ends, -whicli are slightly, if at all, capitate. Length "0026 ; breadth 

 •0006 ; cost® convergent in the middle, radiate towards ends ; inter- 

 mediate free space narrow, except in the middle, where it expands 

 into a narrow stauroform band, slightly wider at the margin than 

 towards the central nodule. (PI. 30, fig. 36.) 



Stauroneis microstauron, Kiitz. Bac, p. 106, T. xxix., fig. 13. 

 — Staujoptera microstauron, Bab. Siissw. Diat., p. 49, T. ix., fig. 7, 



Peatherbed Bog, Co. Dublin. Lough Gill, Co. Kerry. 



Ncmicula crucifera, N. S. Eresh water. 



Yalve linear, oblong, narrow. Length "0026, breadth "0003, 

 Slightly attenuated towards the scarcely capitate ends. Costse con- 

 vergent in the middle, slightly radiate towards the ends ; intermediate 

 free space relatively wide, expanding in the middle into a narrow 

 stauroform band. (PI. 30, fig. 37.) 



This form strongly resembles one described by Schumann as ITavi- 

 eula nodulosa, /3, Die Diat. der Hohen Tatra, p. 77, T. iv., fig. 53. 

 It is, however, longer and narrower, the costae shorter, snd the stauro- 

 form band not so wide. 



Eeatherbed Bog, Co. Dublin. Lough Mourne deposit, Co. An- 

 trim. 



Na/oicula pinnularia, (Cleve). Marine. 

 . Yalve linear, elliptical, ends rounded. Costse strong, nearly paral- 

 lel. Length from -0020 to -00034, breadth from -0006 to -0008. 

 Intermediate free space very narrow, except in the middle, where it 

 expands in a broad strauriform band. (PI. 30, fig. 38.) 



Cleve, Om Svenska och ISTorska Diat., p. 224, T. iv., fig. 1. 



An-an Islands, Stomachs of Ascidians, Roundstone Bay, Stomachs 

 of Ascidians, Broadhaven Bay, Co. Galway. Portmarnock, Co. Dub- 

 lin. 



Navicula scalar is, (Ehr.) Fresh water. 



Yalve linear, elliptical, ends rounded. Length -0014, breadth 

 •0003. Striae nearly parallel ; intermediate free space very narrow, 

 except in the middle, where it expands into a broad stauroform band, 

 reaching the margin. (PI. 30, fig. 39.) 



jSTavicula borealis, var. scalaris, Grunow, Yerhand. der K. K. Zool. 



