O'Meara — Report on the Irish Diatomacece. 283 



Fragilaria maxima, jS". S. Fresh Tvater. 



Prustules very large ; on side view, considerably expanded in the 

 middle, and gradually tapering towards the rounded ends ; striae fine, 

 persistent. (PL 27, fig. 16.) 



Aghold, Co. Wicklow. 



Fragilaria crotonensis, (Eatton.) Presh vrater. 



Frustules long ; margins on front view slightly waved ; on the side 

 "^iew narrow ; very slightly expanded in the middle, and gently attenu- 

 ated towards the slightly capitate ends ; striae fine, persistent. 



This species seems widely diffused, having been found by me in 

 gatherings made by Mr. Mozeley, of H.At.S. Challenger, at Kerguelin's 

 Land. 



Pond, [N'ewcastle Lyons, Co. Dublin. Hill-pond, Greenane, near 

 Eathdrum, Co. Wicklow. Lough Derg, Co. Galway. Bundoran, Co. 

 Donegal. 



Fragilaria tenuicollis, (Heib.) Eresh water. 



Fnistules small ; on front view slightly attenuated at the ends ; on 

 side view narrow, considerably expanded in the middle, and gently 

 attenuated towards the capitate, rounded ends ; striae fine, persistent. 



Heiberg, De Danske Diat., p. 62, T. v., fig. 13. 



Mill-pond, Greenane, near Eathdrum, Co. "^icklow. Malahide, Co. 

 Dublin. 



Fragilaria striatula, (Lyngb.) Marine. 



Prustules short ; on side view linear, rounded at the ends ; striae 

 extremely fine, persistent. 



Lyngbye, Tent.Hydr. Dan., p. 183, T. Ixiii. Wm. Sm.,B.D., Yol.ii., 

 p. 23. Clave, Om Svenska och IS'orska Diat., p. 219. — Fragilaria aurea, 

 Grev. Erit. Flora, p. 403. Harvey's Manual, p. 197. — Grammonema 

 jurgensii, Agardh, Consp., p. 63. Ealfs, in Pritch., p. 778, PL xv., 

 figs. 24, 25. Eab., PL Eur., sect. 1, p. 124. — Grammatonema stratulum, 

 Xiitz. Sp. Alg., p. 187. 



Salt ditch, Arklow, Co. "^'"icklow. Eallybrack, Monkstown, 

 "Kingstown, Co. Dublin. Lame, Eathlin Island, Co. Antrim. 



Fragilaria construetis, (Ehr.) Eresh water. 



Erustules short ; on side view greatly expanded ; ends short and 

 attenuated ; striae fine, persistent. 



Grunow, Yerhand der K. K. Zool. Bot. Gesel., Band xii., 1862, 

 p. 371. Eab., El. Eur., sect. 1, p. 120. — Staurosira construens, Ehr. 

 Mic, T. iii. 3, fig. 8 ; T. iii. 1, fig. 15 ; T. xxxix. 2, fig. 10. Ealfs, 

 in Pritch., p. 791. PI. xv., fig. 5. — Odontidium tabellaria, Wm. Sm., 



11. 1, A. PKOC, PEU. II., VOL. II., SCIP-XCE. 2 N 



