LESSON III 



HKTKROMITA 



When animal or vegetable matter is placed in water and 

 allowed to stand at the ordinary temperature, the well known 

 process called decomposition sooner or later sets in, the 

 water becoming turbid and acquiring a bad sinell. A drop 

 of it examined under the microscope is then found to teem 

 with minute organisms. To one of these, called "the 

 Springing Monad," or in the language of zoology, Hetero- 

 inita rostrata, we must now direct our attention ; it is 

 found in infusion of cod's head which has been allowed to 

 stand for two or three months. 



Heteromita (Fig. 4, a) is considerably smaller than either 

 Amoeba or Haematococcus, being only ^\-^ mm. (joVo irich) 

 in average length. It has a certain resemblance in general 

 form to Hsematococcus, being somewhat ovoidal and pointed 

 at one end. Like H?ematococcus also it has two flagella, 

 but only one of these {fl. i) proceeds from its beak-like 

 anterior end and is directed forwards as the creature swims ; 

 the other (yfl. 2) springs a short distance from the beak, and 

 in the ordinary swimming position is trailed after the 

 organism as in a^ and t"*. Thus in Heteromita, besides an 

 anterior and a posterior end, we may distinguish a ventral 



