NOTES ON SCOTCH FRESH-WATER ALGH, 99 - 
P. duplex Meyen. (P. pertusum Kiitz.). C., 8. 
P. tetras (Ehrnb.) Ralfs. §8. 
. tricornutum heer (Chloroph fran Norska Finmarken. p. 4, f. 3). 
Diam. coenob. 8 87-40 p; diam. cell. 18-15 ». Glen Tummel (1880). 
Fig. 2. 
P, integrum Nag. Fig. 4. 
*P, Sturmit Reinsch ‘(Die Algenflora mitt. Theil. von sprecctth 
. 90, taf. 7, f. 1). Forma aculeis brevioribus. Diam. ccenob. 
a acul.) 52 uw; diam. cell. 10». Fig. 3. Ben Laoigh. 
Ord. SorastREz. 
Sorastrum spinulosum Nig 
overs ome “(Nig.) A.Br. §. Long. cell. 5-7°5 p; 
lat. cell. 3-5-6 
Celastrum phan Nag. Aberdee 
. cambricum Arch. Aberdeen. ey coenob, 42-50 »; diam. 
cell. 19 p. Fig. 14. 
C. microporum Nag 
8. 
C. cubicum Nig. Abes daca 
II.—Proropayta. 
Class Protococcoidea. 
Ophiocytium cochleare (Kichw. ) yA. eas N., Aberdeen. 
Hor nospora mutabilis Bréb. 
Dictyospharium Ehrenber aki “Nig. ©. — Var. at NUTUM, nov. 
“var. fe 16 &17. Var. cellulis minutis globosis. Diam. cell. 
3-3°4 
Nephroe ytinum Agardhianum Nig. §8., M. 
N. Néigeliti Grun. M., Glen Lochaidh. 
Oocystis solitaria Wittr. B., G., M., Orkney Is., Aberdeen. 
Long. 15-20 »; 27° 5-825 pb; lat. 9° 5-11 p; 13°5-17°5 p. = Fig. 12. 
O. Négelit A. Br. §., Ben Chiurn. Long. 28-30 p»; y at. 17 p. 
This is somewhat smaller than the published dimensions of this 
species, and may be O. geminata Niig., which only appears to — 
m former in always being in pairs, and in its smaller size. 
In the specimens observed the cells were in pairs; we do no bie ow 
of any published cama of O. g  / aygng Nag. 
O. apiculata, no 8. O. in familias e 2-4 
cellulis formatas pee ee BPiotivis; diametro duplo longius, 
subapiculatis et incrassatis ad unumquemque polum. Long. cell. 
11-15 p; lat. cell. 5-6 »; diam. fam. 2-cell. 22-24 ». Orkney Is, 
er 
Alg. fra Nov. Sem. p. 26, t. 12, f. 3 et 4); it differs in being rather 
more than twice as long as broad, and in its more oblong shape, 
with thickened pointed ends. 
Ord. ProrococcacEx. 
Pleurococeus vulgaris Menegh. Ben Lawers, &c., common 
hiscia paucispinosa, nov.sp. Fig. 5. T. parva, cellulis 
solitariis vel in familiis ee associatis, subglobosis vel leve sub- 
H 2 
