ILLUSTRATIONS 



PAGE 



Fig. i. FORMS OF BACTERIA . . . .15 



" 2. FLAGELLA OF BACTERIA ... 17 



" 3. SPORES IN BACTERIA .... 20 



Plate I. TUBE CULTURES OF BACTERIA . . 34 



" II. PLATE CULTURES IN PETRI DISHES . 36 



" III. COLONIES OF BACTERIA ... 38 



" IV. A BACTERIAL CULTURE SHOWING THE 



FORMATION OF GAS .... 40 



Fig. 4. STREPTOCOCCI FROM A CULTURE . . 41 



" 5. STAPHYLOCOCCUS FROM A CULTURE . 42 



" 6. BACILLI FROM A CULTURE ... 42 



Plate V. NODULES ON CLOVER ROOTS . . 56 



Fig. 7. NODULE BACTERIA .... 58 



14 8. STREPTOCOCCUS PYOGENES ... 72 



" 9. STAPHYLOCOCCUS PYOGENES ... 73 



ix 



