6 DR. G. 8. WEST ON THE ALGÆ OF 
I. THE PHYTOPLANKTON. 
GENERAL NOTICE. 
The reports upon phytoplankton from the southern hemisphere are so far 
very few. The large lakes of Central Africa have been somewhat extensively 
explored *, but apart from these investigations the only other records are a 
few scanty notes on the limnetie flora of Lake Wakatipu, New Zealand t. 
The present report is therefore of great interest, not only because it constitutes 
the first plankton-investigation of Australian freshwaters, but also on account 
of the extended period over which the collections were made. 
Detailed periodieal investigations of plankton have been carried out in 
several parts of Europe, notably by Lemmermann, Schrüder, Zacharias, and 
Volk in Germany, by Wesenberg-Lund in Denmark, by Chodat and Bachmann 
in Switzerland, and by Huitfeldt-Kaas in Norway. Other less comprehensive 
studies have been made of the lakes of Sweden, Austria, and the British 
Islands. Some excellent work has also been done in the United States, but 
more especially on the zooplankton. 
The collections from the Yan Yean Heservoir show very clearly that the 
Australian plankton, when more fully investigated, will afford an interesting 
comparison with that of the temperate and subtropical regions of the northern 
hemisphere. 
The plankton was collected in all cases along an easterly course, about a 
mile in length, across the middle of the lake, any part of the littoral region 
where weeds came near the surface being avoided. Mr. Hardy forwarded 
me two samples of each collection, one preserved in 3 per cent. formalin and 
the other in 4 per cent. potassium acetate (containing a trace of copper 
acetate). 
In the tabulated aceount which follows, only those Aloæ have been recorded 
which were fixed in the living condition. Empty individuals, obviously dead 
at the time of preservation, have been omitted. 
The METEOROLOGICAL OBSERVATIONS accompanying the collections consisted 
of barometrie and thermometrie records, together with notes on the general 
condition of the weather at the times of collection and during the intervals 
between one collection and the next. 
The barometric readings were taken by Mr. Wilson, the Resident Inspector, 
at 4 р.м. on the dates of collection, at which time a start was made to obtain 
the material, the temperatures being taken during the process of collection. 
The barometer was contained in a house about 100 feet above the surface of 
the lake, which is about 400 feet above sea-level, and the monthly readings 
indicate a remarkable uniformity of atmospheric pressure extending over a 
period of thirteen months. 
* W. Schmidle, in Engl. Bot. Jahrb. xxvi. (1898); xxxii. (1903) ; xxxiii, (1904). б, 8, 
West, in Journ. Linn. Soc., Bot. xxxviii. (1907). 
T E. Lemmermann, in Abh. Nat. Ver. Bremen, Bd. xvi. Heft 2 (1899), pp. 338, 539. 
