410 Proceedings of the Royal Iri&h Academy. 



Navicida galvagensis, ]^. S. Marine. 



Yalve oblong, elliptical, ends narrowed and rounded. Striae cos- 

 tare, radiate; length -0024, breadth -0005. (Plate 34, fig. 12.) 



Salt marsh, near town of Galway ; Stomachs of Ascidians, Broad- 

 haven Bay, Co. Galway. 



Nmictda Solaris, (Grregory). Marine. 



Yalve elliptical, with obtuse rounded ends. Stride fine, linear,, 

 convergent in the middle, and very distinct, radiate towards the ends 

 and less distinct. (Plate 34, fig. 13.) 



Gregory, Q. J. M. S. 1856, Trans., p. 43, PL v., fig. 10. This 

 figure represents the striae as shortened in the middle so as to leave a 

 blank space round the central nodule. And such is the appearance 

 presented by the specimens that have come under my notice ; but 

 when well focused the blank space disappears, and the striae are found 

 to reach the median liae. Ealfs, in Pritch., p. 904. Bab. Fl. Eur. 

 Alg., sect, i., p. 181. 



Ballarena, Co. Derry. Adregoole, Co. Galway. Malahide, Co. 

 Dublin. 



Navicida viridula, (Kiitz. ?) Fresh water. 



Yalve elliptical, lanceolate, sometimes slightly produced. Striae 

 fine, linear, convergent in the middle, radiate towards the ends ; 

 length -0016, breadth -0005. (Plate 34, fig. 14.) 



Kiitz., Bac, p. 91, T. xxx., fig. 47 ; T. iv., figs. 10 and 15. The 

 only one of these figures which at all resembles the present fonn is 

 the last. Ealfs, in Pritch., p. 905. Cleve, Om Svenska och jN'orska 

 Diat., J). 225. Lagerstedt, Sotv. Diat. fran SjDetsbergen och Beeren 

 Eiland, p. 25. — Pinnularia viiidula, "V^^m. Sm., B. D., Yol. i., p. 57, 

 PL xviii., fig. 175. The description is accru-ate, but the figure 

 represents the costae as greatly coarser than they are in reality. The 

 efi^ect is to make this species appear scarcely to differ from Pinnularia 

 gracilis. Lagerstedt indeed remarks, " I have considered it right to 

 unite under the above name (j^avicula viiidula) the two species of 

 Smith, Pinnularia viiidula, and Pinnularia gracilis," p. 25. The 

 striae, however, in the former, are extremely fine, whereas in the 

 latter they are very coarse. Eab. PL Eui'. Alg., sect, i., p. 214. I 

 think it not unlikely that this form is identical with that which 

 Grunow has described as Ifavicula rhyncocephala, var. brevis. 

 Yerhand. der K. K. Zool. Bot. GeselL, Band x., 1860, p. 529, T. iv., 

 fig. Zlc. 



Camolin, Co. Wexford. Lough Gill, Co. Kerry. Killakee, 

 Stream near Clontarf, Co. Dublin .Ditch near town of Sligo, Well, 

 Strokestown, Co. Eoscommon. 



