40 
443. 
444, 
445, 
446, 
447. 
TRANSACTIONS AND PROCEEDINGS OF THE [ Szss. LXIX. 
Genus cHRococcus, Nag. 
Ch. turgidus (Kiitz.), Nig. O—Near Kirkwall ; Hoy. S.—Near 
Lerwick ; Scalloway ; Bressay. Plankton of Lochs Asta and 
Brindister. 
Ch. coherens (Bréb.), Nag. S.—Plankton of Loch Beosetter, 
Bressay. 
Ch. limneticus, Lemm. S.—Plankton of Neugles Water. 
Ch. pallidus, Nig. O.—Near Kirkwall. S.—Near Lerwick. 
Plankton of Loch Beosetter, Bressay. 
Ch. minor (Kiitz.), Nig. S.—Lerwick ; Neugles Water. Plankton 
of Loch Sandy. 
28. 
30. 
EXPLANATION OF PLATES. 
front view of cell (a fronte visa). 
vertical view of cell (a vertice visa). 
side view of cell (a latere visa). 
Puate I. 
. Closteriopsis longissima, Lemm,, var. tropicwm, nob. x 520. 
. Zygnema stellinum (Vauch.), Kiitz., var. cylindrospermum, var. 
by Ses PA0) 
. Crucigenia irreqularis, Wille. x 500. 
. Scenedesmus acutiformis, Schroder, var. Brasiliensis, nob. 
x 520. 
. Closterium exile, sp.n. x 400. 
. Huastrum montanum, sp.n. x 520. 
3 pectinatum, Bréb., var. inevolutum, var. n. xX 430. 
. Xanthidium antilopewm (Bréb. ), Kiitz, var. depauperatum, 
Var.m.  x<o20) 
. Genicularia Spirotenia, De Bary. x 520. 
. Cosmarium goniodes, W. and G. 8S. West, var. variolatum, 
var. n. x400. 
= leve, Rabenh., var. cymatiwm, var.n. x 500. 
9 isthmochondrum, Nordst., var. pergranulatwm, 
var.n. x 400. 
: subcontractum, sp. n. x 400: 
3 Pseudobroomer, Wolle, var. convexwm, var. 0. 
x 400. 
. Pentium margaritaceum (Ehrenb.), Bréb., var. irregularius, 
varnm: Sap 20: 
Prate II, 
. Cosmarium subarctowm (Lagerh.), Racib., forma punctata. 
x 520. 
. Staurastrum boreale, sp.n. x 520. 
a Manfeldtii, Delp. x 520. 
- affine, sp.n. x 520, 
5 polymorphum, Bréb., var. simplex, var. n. 
x 400. 
‘ cyrtocerum, Bréb., var. compactwm, var. Nn. 
x 520. 
i retusum, Turn., var. boreale, var.n. x 400. 
