Nov. 1904. | BOTANICAL SOCIETY OF EDINBURGH a) 
FRESHWATER ALG FROM THE ORKNEYS AND SHETLANDS. 
By W. West, F.LS., and Professor G. S. West, M.A., 
F.LS: 
PAGE 
I. IntTRODUCTION . A : , : ; , ; 3 : 3 
II. PHYTOPLANKTON FROM THE ORKNEYS AND SHETLANDS . : 5 
IIT. GENERAL SysteMATIC ACCOUNT OF THE COLLECTIONS . : 10 
I.—INTRODUCTION. 
With the assistance of a grant from the Royal Society, a 
visit was made during August 1903 to the Orkney and 
Shetland Islands for the purpose of extending our knowlege 
of the distribution of British freshwater alge. 
The Orkneys were visited first, the only islands investi- 
gated being the southern part of Pomona and the northern 
part of Hoy. On Pomona, collections were made from the 
neighbourhood of Kirkwall, Stromness, Finstown, and Loch 
Kirbister, but as the geological formation is mostly Old Red 
Sandstone, these localities are not so good as one would 
otherwise expect. The collections from Hoy were somewhat 
richer, perhaps owing to the fact that some of them were 
made at a greater altitude, but there were few suitable places 
for the occurrence of these plants. 
The only two islands of the Shetland group which could 
be visited were Bressay and the Mainland. The principal 
area examined on Bressay was in the northern part, in the 
immediate vicinity of a group of small lakes known as the 
Beosetter Lochs. The districts investigated on the Mainland 
were to the south and west of Lerwick and to the north and 
east of Scalloway. 
Cultivation of the land is relatively much more extensive 
in both the Orkneys and the Shetlands than in many parts of 
Scotland, and the low-lying districts which were probably at 
one time extensive bogs, are now drained, and alge are con- 
sequently scarce in such localities. Sleeping accommodation 
away from the fishing towns is practically non-existent, and 
in very wet seasons this fact seriously interferes with the 
investigation of many of the more promising districts. 
Another factor which has caused this contribution to be less 
