O'Meaba — Report on the Irinh Dlatomacece. 377 



fine, but easily detected, parallel ; longitudinal strise generally obscure ; 

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

 into a quadrangular area; length about -0008, breadth about "0008. 

 (Plate 31, fig. 55.) 



Grrunow, Verhand. der K. K. Zool. Bot. Gesell, Band x., 1860, 

 T. iv., fig. 4. Grrunow, with a note of doubtfulness, refers the species 

 to IN'aegeli. Schumann, Die Diat. der Hohen Tatra, p. 70. Rab. Fl. 

 Eur. Alg., sect. 1, p. 185. 



Lough Derg, Co. Gal way. Killakee, Co. Dublin. Ditch near 

 town of Galway. 



Navicula incurva, (Greg.) Fresh water. 



Valve slightly incurved in the middle ; ends broadly produced, sub- 

 capitate ; longitudinal sulci parallel, with median line distinct ; striaj 

 obscure; length about -0020, breadth -0005. (Plate 31, fig. 56.) 



Gregory, Q. J. M. S. 1856, p. 8, PL i., fig. 26. Ralfs, in Pritch., 

 p. 893. Eab. PL Eur. Alg., sect, i., p. 203. Donkin, 'E. H. Brit. 

 Diat., p. 38, PL vi., fig. 2. 



Portmarnock, Co. Dublin. Callows, near Ballinasloe, Co. Galway. 



(g) MonilifercB. 



Valves more or less lanceolate; strim ohvioiisly moniliform, not reach- 

 ing the median line ; free intermediate space narrow except in the middle, 

 where it is generally more or less expanded. 



Navicula punctulata, (Wm. Smith.) Brackish or marine. 



Yalve broadly elliptical, with slightly apiculate ends ; intermediate 

 free space narrow, slightly expanded in tlae middle ; strife close, radiate ; 

 length about -0026, breadth -0012. (Plate 32, fig. 1.) 



Wm. Sm., B.D., vol. i., p. 52, PL xvi., fig. 151. Grunow, Verhand. 

 der K. K. Zool. Bot. GeselL, Band x., 1860, p. 537. — Navicula marina, 

 Ralfs, in Pritch., p. 903. Eab. Fl. Eur. Alg., sect, i., p. 202. Donkin, 

 N. H. Brit. Diat., p. 19, PL iii., fig. 5. The last named author 

 remarks, ' ' Although this species is described as marine in the Synop- 

 sis of Prof. Smith, I have never found it in purely marine localities, 

 where its congener N. granulata is found." Some of the undernamed 

 localities in which I have found the species are decidedly marine. 



Stomachs of Ascidians, Belfast Lough, Co. Antrim. Seaweeds, 

 Bannow, Co. "Wexford. Portmarnock, Co. Dublin. Rostrevor, Co. 

 Down. Seaweeds, Kilkee, Co. Clare. Laytown, Co. Meath. Dre- 

 hednamaud, near Castlegregory, Co. Kerry. 



Navicula granulata, (De Brebisson). Marine. 



Valve broadly elliptical, with slightly produced broad rounded 

 ends ; intermediate free space narrow, linear, except at the cen- 



