1897] 



MICROSCOPICAL JOURNAL. 



345 



others connected with water-works to whom the study 

 of algsB and infusoria would be of much value, the writer 

 has tried to reduce the Sedgwick-Rafter method lo its 

 simplest possible elements in order that it may be more 

 generally used. Furthermore, it is often necessary for 

 the sanitary biologist to be provided with a portable out- 

 fit for work in the field. There are many fragile orgaii- 



1.00 



14-0 



— 100 



\-lSO 



\tiys~- 



I 



isms which will not bear transportation to the laboi'atory. 

 Uroglena, for example, a very important and troublesome 

 organism found in water supplies, goes to pieces com- 

 pletely when kept for a sliort time in a stop[)ered bottle, 

 it is, therefore, necessai'y to make the examination of 

 water immediately .ifter the collection of the sample. 

 The chief modification of the method for field woiK 



