O'Meara — Report on the Irish Diatomacece. 335 



at the ends. Strise fine, obscurely punctate, convergent about tbc 

 central nodule, and for a considerable distance from it, towards the 

 -ends straight and radiate. 



Agardli. Conspect., p. 20. Grev. Brit. Flora, p. 412. Harvey's 

 Manual, p. 210. Kiitz. Bac, p. 114, T. xxvii., fig. 6. Wm. Sm., 

 B. D., Vol. ii., p. 74, PL Ivi., fig. 355. Eab. Fl. Eur., sect. 1, p. 268.— 

 Micromega helmintosum, Ealfs, in Pritch., p. 830. 



Howth, Malahide, Co. Dublin. Carnlough Bay, collected by Dr. 

 David Moore. 



Schizonema comoides, (Agardh.) Marine. 



" Prond filiform, simple below, much divided and fasciculated 

 above. Prustules crowded." — Wm. Smith. Frustules small, length about 

 •0010, somewhat rhombic on front view, rounded slightly at the ends. 

 Strice strong and distant at centre, finer and closer towards the end ; 

 ■on front view linear, in outline rounded at ends. 



Agardh. Conspect., p. 19. Harvey's Manual, p. 213. Wm. Sm., 

 B. D., A^ol. ii., p. 75, PI. Ivii., fig. 358. Rab. El. Eur., sect, i., p. 

 268. — Schizonema araneosum, Kiitz. Bac, p. 113, T. xxiv., fig. 2, T. 

 xsv., fig. ix. — Micromega comoides, Ealfs, in Pritch., p. 934. 



Carnlough Bay, Co. Antrim, collected by Dr. David Moore. Howth, 

 Malahide, Co. Dublin. 



Schizonema parasiticum, (Harvey.) Marine. 



" Erond capillary, branched, filaments slightly cohering above. 

 Eamuli short, patent. Mucus often rugose. Erustules croAvded in files, 

 more or less distant. Yalves elliptico-lanceolate, acute. Length of frond 

 5" ; length of frustiile -0011 ; breadth of valve -0002."— Wm. Smith. 

 -Strife extremely fine. Erustule on front view quadi-angular. 



Harvey's Manual, p. 213. Wm. Sm. B. D., Yol. ii., p. 79, PI. lix., 

 fig. 37. Eab. El. Eur., p. 273. — Micromega parasiticum, Ktitz; Bac, 

 p. 116, T. xsvii., fig. 2. Ealfs, in Pritch., p. 932. 



Malahide, Salt HUl, Co. Dublin. 



Schizonema laciniatum, (Harvey.) Marine. 



" Erond filiform, much branched, filaments often adhering into 

 rope-like tufts. Eamuli very long. Erustules numerous, crowded in irre- 

 gular files. Yalves elliptical, somewhat acute. Length of friistule'0018; 

 breadth of valve -00035." — Wm. Smith. Yalves striate ; strife punctate, 

 gently radiate. On front view frustules broader at middle than at 

 ends, ends rounded off ; side view coming largely into sight when 

 observed in front, the innei' margins nearly meeting the connecting 

 membrane, and at the ends receding therefrom. 



On careful inspection of authentic specimens of Schizonema impli- 

 >eatum (Harvey), I find the frustules on side and front view so like one 



