Xl CONTENTS. 



CHAPTER VIII. 



RELATION OF DISEASE TO SOILS AND MANURES. 



Soil which suits the potatoe (205). Diseased in all soils (206). 

 Statement of Mr. Latham (207) ; of Mr. Greatrex (209). Influ- 

 ence of wet soils on the disease (211). Guano and Animal Salts 

 (214). Influence of manures on the disease (216). PAGE 52. 



> CHAPTER IX. 



RELATION OF DISEASE TO FTINGI. 



Berkeley's opinion (217). Fungi common to decaying matter 

 (219). Fungi on decaying tubers (221). Botrytis infestans (223). 

 Fungus in the inside of tubers (226). Different fungi growing 

 in rotten tubers (227 230.) Black fungus on stem (231). 

 Other species of fungi (232, 233) Singular appearance of motion 

 in fungi (234). Fungi influence the disease (237). Fungi fulfil 

 important functions in nature (238 240). Gangrena sicca and 

 humida (241). Tubers infected with fungi perhaps injurious as 

 food (242). PAGE 55. 



CHAPTER X. 



RELATION OF GANGRENE TO ANIMAL PARASITES. 



Numerous species of insects on potatoe plant (244) Acarus (245). 

 Coccinella, ichneumons, flies (247). Aphis (248). PAGE 61. 



CHAPTER XI. 

 APHIS VASTATOR. 



Insect on the potatoe plant (249250) ; its color (252) ; dimen- 

 sions (256 259). Suctorial apparatus (260); head and eyes 

 (261) ; abdomen and tubercles (262) ; pupa (263) ; imago, or per- 



