102 



MISSOURI BOTANICAL GARDEN. 



which the content is broken up into parts. 20, 21, The same vesicles 



drawn on a larger scale. 



fungus 



destroyed, the walls of the vesicle and hyphae remaining. 23, A 

 host cell which has collapsed in which the remains of the fungus are 

 still present. 24, Nuclei of the host cell before they become amoeboid 

 in form. 25, Stages of nuclei found in the digestive cells. 26, Very 

 late stages of degeneration of nuclei just before their final disappear- 



ance. 





Plates 13, 14. — Myrica cerifi 



28, Life-sized tubercles as they 



are found in the clusters. 29, A longitudinal section of a tubercle 

 showing the infected region and the various tissues of the tubercle. 

 30, Several uninfected cells showing the cell content. 31, Cells indi- 

 cating the method by which internal infection takes place. 32, Cells 

 showing the large number of hyphae which pass through the walls to 

 infect the cell. 33, Several cells of the infected region showing 

 young and old stages of the fungus where the branches of the hyphae 

 have enlarged into club-shaped structures. 34, A portion of mycelial 

 thread showing the nuclei. 35, The club-shaped ends of the hyphae. 

 36, The same but older structures where the nuclei have passed into 

 them from the mycelium. 37, A stage where the host cell and the 



nucleus begin to disintegrate. 



fungu 



38, Several degenerating nuclei found in host cells. 



