THE AMERICAN 



MONTHLY 



Synura. 



By GEORGE C WHIPPLE, 



BOSTON, MASS. 



[See iSth Ann. Rep. Boston Water Board, 1893.] 



Of the thirty or more genera of infusoria which are 

 found in the water supplies of Massachusetts, there are 

 but fifteen which may be said to be commonly found in 

 large numbers. Eight of these common forms belong 

 to one order, and six of them belong to one family of 

 that order, if we adopt the classification of Mr. W. 

 Saville Kent.* 



The special characteristic of this family, the Cliryso- 

 monadidsB, is the presence of lateral pigment bands. 

 These color bands, in addition to their distinctive tint, 

 are apparently of firmer consistency than the surround- 

 ing transparent protoplasm, and bear a very considerable 

 resemblance to the coloring matter of the Diatomacese," 



But the most important fact about the Chrysomona- 

 didsB, from a sanitary point of view, is that almost every 

 one of them has given rise to very disagreeable and some- 

 times extremely offensive tasts and odors in the waters 

 in which they have been found. Uroglena, Cryptomonas, 

 and Chloromonas have already acquired quite unenvi- 

 able reputations. To these may be added Synura uvella 

 and Dinobryon. It is noticed also that there is a simi- 

 larity between the tastes produced by some of the or- 

 ganisms of this group and those produced by certain 

 diatoms. Cryptomonas, for instance, produces a sweet- 



* A manual of the Infusoria, I, 212. 



