8S 



5th August, 1890. 



Gentleuieii, — I have the houoi' to transmit Progress Report by 

 Mr. Whitelegge on Alg;e received from the Geological Survey 

 Department, and handed to him for examination, and to recom- 

 mend that it be published in the " Records," and a copy forwarded 

 to the Department. 



I liave the honor to he, Gentlemen, 



Your Obedient Servant, 



Ed. p. Ramsay, Curator. 



To the Trustees of the Australian Museum. 



Australian Museum, 



4th xUigust, 1890. 

 To the Curator. 



Sir, — I have the honor to report that some time 

 ago I received from the Acting Curator a bottle containing a 

 green unicellular Alga, obtained by Mr. David, the Acting- 

 Government Geologist, from the Maitland Waterworks, with 

 instructions from the former to send in a Progress Report for 

 the information of the Trustees. 



It appears that this particular Alga exists at certain seasons 

 in such numbers as to seriously interfere with the pumping of 

 the water, which it would pi'obably render unpalatable, if not 

 unlit for consumption. 



The plants are exceedingly small, somewhat ovoid in shape, 

 and of a light pea-green colour. When found in large numbers 

 they give off a very unpleasant and fa'tid odor, like that of many 

 other plants rich in protoplasm, such as Nitella and Chara. The 

 plant is evidently closely allied to, if not identical with 

 Chlainydomonas ptdvitiCtdus of Ehrenberg, but until the various 

 stages of its life-history are known, it would be unsafe to give a 

 definite opinion as to its specific identity. From what I have 

 seen of the same plant near Sydney, it passses some weeks in a 

 free swimming condition, afterwards it loses its cilia and rises to 

 the surface of the water, forming a thick scum of green powder. 

 This phase evidently represents one of the resting stages of the 

 plant. When found in this condition it seems to repel the water 

 and appears quite dry ; by the action of the wind it is blown to 

 the sides of the dam, where it often accumulates to a depth of 

 several inches. It is probable, that before the plants resume 

 active growth again, a kind of drying process is necessary, and 

 tliat they rest on the mud until the ensuing rainy season. 



