322 THE AMERICAN MONTHLY [Oct. 



with its accompanying large expense, would result only 

 in intensifying the trouble. Neither will filtration of 

 the waters before they enter the reservoirs answer. In 

 fact he thinks that the Asterionella is the chief cause of 

 the trouble. I have taken the above facts from Prof. 

 Leed's report and commend it to the attention of every 

 one interested in pure drinking water. 



Prof, Leeds says that the Asterionella flavor is from a 

 substance which in many of its properties resembles 

 trimethylamine, and trimethylamine occurs somewhat 

 widely distributed in nature. Thus, for instance, it is 

 found in various plants, as the Cheuopoderium vulvaria, 

 Annica montana, Murcurialis annua, the bloom of the 

 hawthorn, that of the wild cherry, and of the pear, as 

 well as in ergot, and other fungi parasitic on cereals. It 

 also occurs in various animal liquids, and especially in 

 herring-brine. It is likewise found as a product of de- 

 composition of various alkaloids, and amongst the pro- 

 ducts of dry distilllation of nitrogenous, organic matter 

 and of wood. It has a powerful and penetrating char- 

 acteristic fish-like smell. I have found it as a character- 

 istic twice of Asterionella in the season when ovulation 

 takes place and it seems to be characteristic of the en- 

 largement of the oil globules as they are called, or ova 

 as I designate them. 



The reproduction of the Bacillaria seems to be this: 

 As the individual is found, it contains, besides endo- 

 chrome, or olive-colored matter, large oil globules which 

 are transparent and look extremely like drops of oil. 

 These are colorless and permanent so that when the 

 Bacillarian individual is dried up the endochrome withers 

 away but the oil globule stays and when the individual 

 is acted upon by acid, the oil globule is not so readily 

 acted upon. These I shall show are ova or female organs, 

 as the individual opens there appear certain minute dots 

 which are extremely active in motion. They increase in 



