28 METHODS OF EXAMINING FECES FOR PARASITISM. 



Comparative tests of three methods in examination of dog fcces. 



An examination of the above table shows that the results obtained 

 by the use of the waiter's method and of Bass's method without the 

 step involving the use of the solution of 1.050 specific gravity, are 

 on the whole superior to those obtained by the use of Bass's method. 

 Dock and Bass (1910) state of Bass's method: 



Gage and Bass conclude, after this extensive experience [the examination of 

 the feces of 315 students by the smear method, by sedimentation and centrifug- 

 ing, and by Bass's method], that for all practical purposes washing with water 

 alone is all that is necessary and that the washing with calciuni-chlorid 

 solution is unnecessary except for special purposes. 



The fact that the use of the strong calcium chlorid solution gives 

 at times better results than the use of water alone is the writer's 

 warrant for making use of it in one centrifuge tube to check the 

 findings from the other tube. 



GARRISON'S CALCIUM CHLORID SEDIMENTATION METHOD. 



Garrison's method of using calcium chlorid and sedimenting instead 

 of centrifuging has come to the writer's attention too recently to 

 permit of adequate tests. A test made by sedimenting in a centrifuge 

 tube instead of centrifuging did not give as good results as cen- 

 trifuging. Sedimenting has the disadvantage of being slower than 

 centrifuging. 



TELEMANN'S ETHER HYDROCHLORIC ACID METHOD. 



A number of tests were made to determine the applicability of 

 Telemann's (1908) chemical methods to the examination of feces. 

 Telemann himself states that he has found his method satisfactory in 

 a large series of human and animal feces. He does not specify 

 what animals are included in the series, but his statement may be 

 believed in any case. At the same time, the tests made in this 

 laboratory indicate that his success was due more to the use of the 

 hair sieve than to the use of chemicals. The latter probably did 



