PROCURING OBJECTS. 83 



In reference to obtaining infusoria, some persons imagine 

 that if they procure a portion of fetid ditch-water, or take 

 a few flowers, &c., and macerate them in water, they will be 

 furnished in a few days with all the varieties they may desire ; 

 but this is not the case. Infusoria will of course be found, 

 but they will be only of the most ordinary kinds. To obtain 

 those of higher interest, some degree of skill is required. 

 Many remarkable species have been taken in meadow-trenches 

 in the slowly running water, after a summer shower, especially 

 about the time that the first crop of hay was mown. Among 

 healthy water-plants, the various kinds of Vorticellina (Sten- 

 tors and Vorticellsej or trumpet and bell-shaped infusoria), and 

 Rotatoria (wheel-animalcules), may be sought for with success. 

 The stems of aquatic plants have often the appearance, to the 

 naked eye, of being encased with mouldiness, or rancor, which 

 on being examined with the microscope, proves to be an ex- 

 tensive colony of arborescent animalcules. The dust-like 

 stratum sometimes seen on the surface of ponds, and the 

 shining film which sometimes covers water-plants, assuming 

 various hues of red, brown, yellow, green, and blue, is caused 

 by the presence of infusoria, some of which are very beautiful. 

 Many species live in the clean fresh water of rivers, lakes, and 

 springs; and the brine of the ocean, Imewise, as well as the 

 mould on the surface of the earth, has its microscopic inhabi- 

 tants. 



In order to procure animalculse, provide yourself with a 

 number of clean, wide-mouthed, glass phials, fitted with proper 

 corks, not glass stoppers, so that the air may have access to 

 them, at least to some extent. Have also a rod, or walking- 

 cane, which may be prepared with a spring-hook and ferule for 

 fastening a phial on its end, although a piece of twine is a 

 good substitute. On reaching the pond, &c., carry the phial 

 (attached to the rod) in an inverted position, and when at 



