O'Meara — Bepoi't on the Irish Diatomacew. 395 



tinder the name of Xavicula notabilis, passing into the variety expleta, 

 by Schmidt, Atlas der Diat., T. viii., figs. 50, 51 and 52. It seems 

 to be perfectly distinct from l^avicnla notabilis, and deserving of 

 being marked by a distinct specific name. 



Stomachs of Ascidians, Eoimdstone Bay ; Stomachs of Ascidians, 

 Broadhaven Bay ; Arran Islands, Co. Galway. 



Navicula cynthia, (Schmidt). Marine. 



Yalves broadly elliptical; ends rounded ; median compartment nar- 

 row, linear, slightly incurved at the ends, and slightly constricted in 

 the middle compartment at either side, narrow, arcuate, unstriate ; 

 marginal striate band broad ; striae fine, close, linear, slightly radiate, 

 divided into two nearly equal parts bv a longitudinal sulcus ; length 

 •0012, breadth -0007. (Plate 33, fig. 10.) 



Schmidt, Atlas der Diat., T. viii., fig. 41. This figure does not 

 indicate the longitudinal sulcus which in my specimens divides the mar- 

 ginal band of striae into two compartments ; still I am disposed to 

 regard the present form as at best a variety of the form described by 

 Schmidt. 



Stomachs of Ascidians, Broadliaven Bay, Co. Galway. 



Navicula sansegana, (Grunow). Marine. 

 Yalve linear, elliptical, ends rounded ; median compartment narrow, 

 linear throughout ; compartments on either side narrow, very slightly 

 arcuate, striate ; marginal striate band relatively broad ; striae linear, 

 sub-distant, parallel in the middle, slightly radiate towards the ends ; 

 length -0020, breadth -0009. (Plate 33, fig. 11.) 



Schmidt, Atlas der Diat., T. viii., fig. 27, who attributes the spe- 

 cies to Grunow, but I cannot find it noticed in any of the many papers 

 of that author which I have had the opportunity of consulting. 



Stomachs of Ascidians, Broadhaven Bay, Co. Galway. 



Navicula arrcmiensis, N. S. Marine. 



Yalve small, elliptical ; median compartment narrow, slightly con- 

 stricted in the middle, slightly incurved at the ends ; compartments at • 

 either side narrow, arcuate, striate ; marginal band of stiiae narrow ; 

 striae strongly costate, distant, nearly linear. Length -0012, breadth 

 •0006. (Plate 33, fig. 12.) 



Arran Islands, Co. Galway. 



Navicula schmidtii, N. S. Marine. 



Yalve broadly elliptical, ends rounded ; middle compartment nar- 

 row, linear, strongly marked ; very slightly constricted in the middle, 

 very slightly incurved at the ends ; compartments at cither side 



K.I.A. PROC, SEK. II., VOL, II., SCIENCE. 2 U 



