I 



THE ANIMAL CELL, 

 ITS MORPHOLOaY AND PHYSIOLOGY 



A. — The UincELLULAE Animals 

 Example 1. — The Protozoa 



Material. — Specimens may be obtained in any of the 

 following ways : by skimming the surface of the mud 

 in the bottom of a pond or a slow -running ditch or 

 brook ; by scraping the under surface of the leaves of 

 water plants, as pond-lilies, duck-weed, etc. ; by squeez- 

 ing the water out of clumps of fresh-water or marine 

 algse, or out of damp sphagnum moss ; by tying a 

 small bag of bolting -cloth or of fine muslin over the 

 mouth of a Avater-tap, allowing the water to run slowly 

 through the bag for fifteen minutes to an hour, then 

 turning the bag wrong side out and rinsing the col- 

 lected sediment into a dish containing a small amount 

 of water; by searching, under the microscope, the moist 

 green film found growing on the surface of flower-pots, 

 trunks of trees, and on the bricks or stones in the foun- 

 dations of buildings ; by examining the fluid found in 

 the mantle-cavity of oysters and clams ; by rinsing in 

 artificial sea -water the gills of unboiled lobsters; by 

 scraping the tongue and the roof of the mouth of frogs 



