34 
326. 
327. 
328. 
329. 
330. 
dal. 
BBDy 
334. 
335. 
336. 
307. 
308. 
Deg. 
340. 
d4l. 
m othbiyhy by 
TRANSACTIONS AND PROCEEDINGS OF THE [ Sess. LXIX. 
Family EvNorTiaces. 
Genus EUNOTIA, Ehrenb. 
. E. pectinalis (Kitz), Rabenh. O.—Near Kirkwall; Finstown ; 
Hoy. S.—Near Lerwick; Scalloway. - 
. prerwpta, Ehrenb., forma curta, V. H. O.—Hoy. 
Var. inflata, Grun. O.—Near Kirkwall. 
Arcus, Ehrenb. O.—Hoy. 
. gracilis (Ehrenb,), Rabenh. S.—Near Lerwick; near Scalloway. 
. major (W.Sm.), Rabenh. O.—Hoy. S.—Near Scalloway. 
. diodon, Ehrenb. S.—Near Scalloway ; Neugles Water. 
. lunaris (Ehrenb.), Grun. O,—Near Finstown. S.—Lerwick ; 
near Scalloway. 
. biceps (W. Sm.) G. S. West. [Synedra biceps, W. Sm. ; 
E. flexuosa, Kiitz, var. bicapitata, Grun.] S.—Bressay, in 
ditches, 
Family ACHNANTHACE. 
Genus ACHNANTHES, Bory. 
A. coarctata (Bréb.), Grun. O.—Plankton of Loch Kirbister. 
A. flexella (Kitz), Bréb. [Cocconeis Thwaitesu, W. Sm.] O.— 
Kirkwall; Hoy. S.—Near Lerwick ; Bressay. 
A. Biasolettiana, Grun. O.—Well at Finstown. 
A. exilis, Kiitz. O.—Near Kirkwall; Hoy. S.—Near Lerwick ; 
Neugles Water. 
A. lanceolata (Bréb.), Grun. O.—Finstown. S.—Near Scalloway. 
Family CoccoNEIDACE. 
Genus COCCONEIS, Ehrenb. 
C. Placentula, Ehrenb. 0O.—Stromness, S.—Neugles Water. 
Plankton of Loch Asta. 
C. Pediculus, Ehrenb. O.—Kirkwall; Finstown ; Hoy. 
Family NavICULACE. 
Genus NAVICULA, Bory. 
N. nobilis (Ehrenb.), Kiitz. O—Near Kirkwall (very abundant 
among Hremosphera viridis and Tetmemorus granulatus) ; Hoy- 
S.—Near Lerwick ; near Scalloway. 
N. major, Kitz. OW—Kirkwall; Hoy. S—Plankton of Loch 
Asta. Bressay, in ditches, and in the plankton of Loch 
Beosetter. 
N. viridis, Kitz. O.—Near Kirkwall; Hoy. Plankton of Loch 
Kirbister, S.—Near Lerwick ; near Scalloway ; Neugles Water- 
Plankton of Loch Clickhimin, and also of Loch Beosetter, 
Bressay. 
N. lata, Bréb. O.—Kirkwall. 
N. alpina (W. Sm.), Ralfs. O.—Near Kirkwall. S—Near 
Lerwick ; near Scalloway. Plankton of Loch Beosetter, Bressay. 
In some of the collections this species was very abundant. 
N. divergens (W. Sm.), Ralfs. O.—W. of Kirkwall. 
N. Brebissonii, Kitz. O.—Kirkwall Plankton of Loch Kirbister- 
N. Tabellaria (Ehrenb.), Kiitz. O.—Kirkwall; Finstown ; Hoy. 
N. gtbba (Ehrenb.), Kiitz. O—Near Kirkwall; Hoy. S.— 
Scalloway. 
