COPROZOIC PROTOZOA 63 



vent the water of condensation falling upon the agar. From such 

 cultures pure lines may be started by isolation of a single indi- 

 vidual under the binocular. 



Many coprozoic flagellates and amoebae will do well in a weak 

 solution of egg albumen in water, hay infusion, or in a boiled 

 watery extract of feces. 



The following media were used by Bunting (1926) in the study 

 of Tetramitus ro stratus. 



Spinach Extract 



Powdered spinach 10 gms. 



Distilled water 400 cc. 



Boil for thirty minutes on water bath with constant stirring; filter 

 through cotton cloth lining a heated funnel; adjust filtrate to original 

 volume; add 0.01% Witte's peptone and 0.01% dextrose; refilter, tube and 

 sterilize (Arnold). 



An excellent solid medium can be made from the above by the addition 

 of 1.5% agar. 



Modified Sellard's Medium 



Witte's peptone i gm. 



Dextrose i gm. 



Distilled water 100 cc. 



A solid medium may be made up by adding 1.5% agar to the Modified 

 Sellard's fluid. These media are given fractional sterilization in an Arnold 

 sterilizer. 



Modified Wherry's (1913) Ovo-Mucoid Medium 



Hen's ^gg white 30 cc. 



Distilled water 300 cc. 



Yolk (optional) 1.5 cc. 



The yolk was not always included in the formula and is better omitted 

 if the medium is used for handing drops. This medium is given fractional 

 sterilization in the Arnold and when cool the 0.5% yolk is added and thor- 

 oughly mixed with the ^gg white before tubing. 



PROBLEMS AND METHODS 



The problem of primary importance in dealing with organisms 

 which appear in a stool is to determine whether they are of 

 entozoic habit or whether they are coprozoic. As indicated above, 

 probably the best way to distinguish between the two is to let the 

 stool remain at room temperature for several days. Vegetative 

 forms of entozoic organisms will decrease rapidly at room temper- 

 ature whereas coprozoic organisms will multiply rapidly and show 

 marked increase in numbers. 



