304 Proceedings of the Royal Irish Academy. 
species as Pinnularia termes, Ehr.—Navicula mesolepta, var. nodulosa, 
Grunow, Verhand. der K. K. Zool. Bot. Gesell., Band x., 1860, p. 320. 
Featherbed Bog, Co. Dublin. Camolin, Co. Wexford. 
Navicula microstauron, (Ehr.) Fresh water. 
Valve linear, oblong, attenuated towards the broadly rounded 
ends, which are slightly, if at all, capitate. Length 0026; breadth 
"0006 ; coste convergent in the middle, radiate towards ends; inter- 
mediate free space narrow, except in the middle, where it expands 
into a narrow stauroform band, slightly wider at the margin than 
towards the central nodule. (Pl. 380, fig. 36.) 
Stauroneis microstauron, Kiitz. Bac., p. 106, T. xxix., fig. 13. 
—Stauroptera microstauron, Rab. Siissw. Diat., p. 49, T. ix., fig. 7. 
Featherbed Bog, Co. Dublin. Lough Gill, Co. Kerry. 
Navicula crucifera, N.S. Fresh water. 
Valve linear, oblong, narrow. Length ‘0026, breadth -0003. 
Slightly attenuated towards the scarcely capitate ends. Cost con- 
vergent in the middle, sightly radiate towards the ends ; intermediate 
free space relatively wide, expanding in the middle into a narrow 
stauroform band. (Pl. 30, fig. 37.) 
This form strongly resembles one described by Schumann as Navyi- 
cula nodulosa, 8, Die Diat. der Hohen Tatra, p. 77, T. iv., fig. 53. 
It is, however, longer and narrower, the coste shorter, snd the stauro- 
form band not so wide. 
Featherbed Bog, Co. Dublin. Lough Mourne deposit, Co. An- 
trim. 
Navicula pinnularia, (Cleve). Marine. 
Valve linear, elliptical, ends rounded. Coste strong, nearly paral- 
lel. Length from ‘0020 to ‘00034, breadth from -0006 to -0008. 
Intermediate free space very narrow, except in the middle, where it 
expands in a broad strauriform band. (PI. 30, fig. 38.) 
Cleve, Om Svenska och Norska Diat., p. 224, T. iv., fig. 1. 
Arran Islands, Stomachs of Ascidians, Roundstone Bay, Stomachs 
of Ascidians, Broadhaven Bay, Co. Galway. Portmarnock, Co. Dub- 
Navicula scalaris, (Ehr.) Fresh water. 
Valve linear, elliptical, ends rounded. Length -0014, breadth 
‘0003. Striz nearly parallel; intermediate free space very narrow, 
except in the middle, where it expands into a broad stauroform band, 
reaching the margin. (Pl. 30, fig. 39.) 
Navicula borealis, var. scalaris, Grunow, Verhand. der K. K. Zool. 
