O'Meara — Report on the Irish Liatomacece. 389 



NavicuJa franciscce., IS". S. Marine. 



Yalve nearly orbicular ; marginal band of strife nai'row ; median 

 band of strife narrow, distant fi'om median line, leaving a lanceolate, 

 unstriate space between the inner margins ; intermediate space 

 between the inner and outer bands of striae broad, luistriate ; strife 

 moniliform, parallel in the middle, radiate towards tbe ends ; length. 

 •0033, breadth -0030. (Pkte 32, fig. 30.) 



Stomachs of Ascidians, Roirndstone Bay, Co. Galway. 



Naiicula liilernica, IST. S. Marine. 



Yalve elliptical oblong ; marginal band of strife narrow, slightly 

 broader in the middle than at the ends ; inner band of strife narrow, 

 roundly expanded at the ends ; intermediate space between the inner 

 and outer bands of strife broad, ornamented with irregularly disposed 

 distinct puncta ; strife of the marginal band linear, with moniliform striae 

 interposed, parallel in the middle, radiate towards the ends ; striae of 

 the inner band punctate, parallel. (Plate 32, fig. 31.) 



Stomachs of Ascidians, Roundstone Bay ; Ai-ran Islands, Co. Gal- 

 way. 



Navicida nitescens. (Gregory). Marine. 



Yalve elliptical, lanceolate ; strife apparently strongly costate,^ 

 divided by a longitudinal sulcus into two nearly ecj[ual compartments ; 

 free space between the inner margins of the inner bands of strife nar- 

 row, lanceolate ; slightly expanded in the middle. (Plate 32, fig. 32.) 



Ptalfs, in Pritch., p. 898. Ptab. Fl. Eur. Alg. sect, i., p. 179. 

 Donkin, X. H. Brit. Diat., p. 8, PI. i. fig. 7. — Kavicula smithii, var. 

 nitescens, Gregory, Diat. of Clyde, p. 487, PI. ix., fig. 16. — Pinnularia 

 arraniensis, O'Meara, Q,. J. M. S., 1867, p. 116, PI. v., fig. 6. 



Arran Islands. Stomachs of Ascidians, Eoundstone Bay ; sto- 

 machs of Ascidians, Broadhaven Bay, Co. Galway. 



Navicula ricTiardsoniana, IST. S. Marine. 



Yalve naiTow, elliptical ; ends rounded ; inner band of strife broad 

 outer band of strife very narrow ; strife strongly costate, sub-distant, 

 radiate; length -0024. breadth -0006. _(PlateV2, fig. 33.) 



This form strongly resembles Kavicula nitescens, but differs so 

 much as to be entitled to be regarded as a distinct species. 



Stomachs of Ascidians, Broadhaven Bay, Co. Galway. 



Navicula stolxsiana, N^. S. Marine. 



Yalve large, rhombic, lanceolate ; marginal striate band wide ; 

 inner striate band narrow, elevated above the surface ; free space in- 



