84 BIOLOGY 



Spread a bit of any decaying matter (the decaying pond weeds will do very 

 well, or a bit of tartar scraped from the teetlj) in as thin a film as possible 

 upon a slide, dry in air or fix by heat by passing it twice through a gas flame. 

 When thoroughly dry flood the slide with a solution of f uchsin or methylene* 

 blue and allow to stain for two to five minutes. Then wash the stain off in 

 running water, and place a cover glass over the stained mass on the slide. 

 The bacteria appear under a high power objective as minute stained dots, 

 or short rods. They are much smaller than yeast cells, and are only just 

 visible with a 1/6 inch objective. Higher powers are needed to study 

 them. 



BOOKS FOR REFERENCE 



BRONN, Klassen und Ordnung des Thierreichs, C. F. Winter, Leipzig. 



DAVIDSON, Practical Zoology, American Book Company, New York. 



HEGNER, Introduction to Zoology, Macmillan Co., New York. 



HEGNER, College Zoology, Macmillan Co., New York. 



HERTWIG, Manual of Zoology, translated by Kingsley, Henry Holt 

 & Co., New York. 



JORDAN and PRICE, Animal Structures, D. Appleton Company, New 

 York. 



MARSHALL, Microbiology, P. Blakiston's Son & Co., Philadelphia. 



PARK, Pathogenic Bacteria and Protozoa, Lea & Febiger, New York. 



PARKER, Elementary Biology, Macmillan Co., New York. 



PARKER and HASWELL, Text-book of Zoology, Macmillan Co., New 

 York. 



PRATT, Invertebrate Zoology, Ginn & Co., Boston. 



*Methylene blue solution is made as follows: 



Saturated alcoholic solution of methylene blue . . . 15 c. c. 



Potassium hydrate (1 : 10,000) 50 c. c. 



To make a 1 : 10,000 solution of KOH, add 1 c. c. of a 10% solution to 

 99 c. c. of water and then add 5 c. c. of this to 45 c. c. of water. 



