SCOTTISH FRESHWATER PLANKTON. 
(say 
qn 
a 
EXPLANATION OF THE PLATES. 
a, a’ = front view (a fronte visa). 
b = vertical view (a vertice visa). 
d = basal view of semicell (a basi visa). 
Prater 14. 
‘Figs. 1,2. Genicularia elegans, sp. n. x 470. . 
3. Closterium Cynthia, De Not., var. curvatissimum, var.n. X 470. 
4. Staurastrum conspicuuwm, sp.n. xX 470. 
5. ” aristiferum, Ralfs, var. protuberans, var.n. X 470. 
6. ” brevispinum, Bréb., var. retusum, Borge. xX 384. 
7. ” verticillatum, Arch. x 470. 
8,9. Arthrodesmus crassus, sp.n. X 470. 
Prats 15. 
Figs. 1,2. Micrasterias Murrayi, sp.n. X 384. 
3. ” ” var. triquetra.  X 470. 
4, Euastrum verrucosum, Ehrenb., var. planctonicum, var.n. X 884. 
5. Cosmarium Capitulum, Roy & Biss., var. granlandicum, Borges. 
x 470. 
6. - abbreviatum, Racib., var. x 470. 
7. » Lundellii, Delp., var. ethiopicum, West & G. 8, West. 
x 470. 
Puats 16. 
Fig. 1. Xanthidium antilopeum, Kiitz., forma. x 470. 
2, 3. ” controversum, West & G. S. West, var. planctonicum, 
var.n. xX 470. 
4, 5. ” subhastiferum, West. x 384. 
6. » ” var. Murrayi, var.n. X 384. 
7. ” tetracentrotum, Wolle, forma. xX 470. 
8. Staurastrum megacanthum, Lund., var. scoticum, var.n. xX 470. 
9. ” Dickiei, Ralfs, var. rhomboideum, var.n. x 470. 
10. » angulatum, West, var. planctonicum, var.n. X 470, 
1], 12. » lunatum, Ralfs, var. planctonicum, var. n. X 470. 
Puate 17. 
Fig. 1. Staurastrum jaculiferum, West, forma biradiata (= Arthrodesmus 
longicornis, Roy). x 470. 
2,3. Staurustrum jaculiferum, West, forma triradiata. X 470. 
4. ” » forma quadriradiata. X 470. 
3. ” ” var. excavatum, var.n. X 470. 
6-8. var. subexcavatum, var,n. X 384. 
2,10. Arthrocesmus quiriferus, sp. n. x 470. 
1. Staurastrum mucronatum, Ralfs, var. subtriangulare, var.n. X 470, 
12, ” curvatum, West. x 470. 
13. » cuspidatum, Bréb., var. maximum, West. x 470. 
LINN. JOURN.—BoTANY, VOL, XXXV. 27 
