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hardly microscopic. Below the surface of the mud an extensive 

 root system is produced ; the roots branch dichotomously, and 

 extend to a considerable distance, often reaching a length of 

 '6 mm. Here it breaks up into pieces, each surrounding itself 

 with a somewhat thick cell and becomes a hypnospore. This may 

 develop in various ways. Dr. Cooke, translating from a foreign 

 :author, says : " If removed from the soil and placed in water, the 

 cell becomes a subterranean zoosporangium " which does not 

 seem a very clear statement. Mr. Burton said in conclusion 

 there is much about this little alga which is at present 

 unknown, including the exact form in which it exists during the 

 long periods while its habitat is covered with water, preventing 

 the development of what we look upon as the definite plant, 

 Botrifdiuiii granidatumi. 



Mr. R. Paulson said the question really was, does the alga 

 exist all the time, or has it the power of very rapid propagation 

 when conditions are suitable ? Referring to the quotations from 

 foreign authors, he suggested that it would be best to go to the 

 originals, as the translator might not have clearly expressed the 

 authors' meanings. 



Mr. A. E. Hilton asked for information as to the number of 

 nuclei present, and the nature, composition and thickness of the 

 cell walls. He suggested that Botrydium was possibly distantly 

 related to his own pets, the Mycetozoa. 



Mr. Burton, replying, said he understood Mr. Paulson to say 

 that if the organism did exist all these years, we should find it. 

 But we possibly have it in an unrecognised motile form. If it 

 did not so exist, it was very remarkable how it could propagate 

 itself over so large an area in so short a time. A friend had said 

 that it was not common, but when it was found advised him to 

 take a wheelbarrow and shovel. The organisms are multinucleate. 

 The spores are small rounded bodies with a very thin wall, and 

 two, three or four small chlorophyll corpuscles. The spores 

 begin to develop on the day after they are liberated. He suggested 

 that there were a few plants growing at the edge of the water, 

 and that when the draining was commenced the edge of the 

 water, in retiring, drew the spores with it, and so over the whole 

 space as their development continued. 



The Chairman, in proposing a vote of thanks to Mr. Burton, 

 said it frequently happened that the discussion following a paper 



