ALG/E. n; 



such cases it is best to take up a small portion in a 

 white glass bottle, and look through it with a pocket- 

 lens, when well-defined forms will be detected, though 

 too small to admit of their structure being seen. A 

 good microscope will at once show the myriads of 

 beautiful green bodies — true plants — which are 

 present. To convey some idea of their number, 

 Mr. W. Phillips took a common pin, put the head of it 

 in water collected in Newton Mere, and thus obtained 

 a small drop, and, on placing this drop under a micro- 

 scope, he could clearly count three hundred individual 

 plants. It must be left to the reader to calculate 

 how many must be present to colour the water of a 

 mere one hundred and fifteen acres in extent. It 

 only remains to add that the particular species of 

 algae found in the Shropshire meres at the time of 

 "breaking" were the Riviilaria echinata, in great 

 quantity, one or two forms oi Anabcena with Aphani- 

 somenoji fios-aqucB, just as in Scotland, but with the 

 addition of another minute species, CcelospJiceruim 

 Kutzingianuin. We have yet to ascertain the reason 

 for the sudden and enormous influx of the Rividaria 

 and AiiabcBna at this particular season of the year, 

 and its persistency for a long period in Britain, whilst 

 so transient in Prussia. Here again, as in so many 

 other instances amongst the lower forms of vegetable 

 life, we recognize a deficiency in our knowledge of 

 the life-history of these minute organisms ; whereas, 

 if we w^ere able to trace them through their whole 

 career of development and reproduction, we might 

 comprehend, and appreciate at its true value, as a 

 perfectly natural consequence, this sudden appear- 



