PLATE 17 

 A-H. — Verticillium albo-atrum: 



A, Simple conidiophores and conidia. X 1,000. 



B, Same showing, respectively, the collection of the conidia on the sterigma in 

 irregular aggregations in dry air, and in water drops in humid air. X 1,000. 



C, Verticillate conidiophores bearing one and three whorls, or virtels, of branches, 

 respectively. X500. 



D, Verticillate conidiophore having conidial heads, from humid environment — 

 that is, moistiu-e drops in which the conidia float as in figure B. This is the so-called 

 Acrostalagmus type of conidial head. X500. 



E, Mycelium of V. albo-atrum in the vascular ducts of an okra plant inoculated 

 with this fungus. X250. 



F, H, Germinating conidia: F, Xsoo; H, Xi,ooo. 



G, Swollen, sclerotia-like mycelium. X500. 



I-M. — Fusarium vasinfectwm: 



I, Terminal, intercalary and conidial chlamydospores. i, Germinating terminal 

 chlamydospore. 2, Free mature chlamydospore. X 1,000. 

 K, Germinating macroconidium. X 1,000. 



1-,, F. vasinfectumirova.okxa-WAt. Twelve macroconidia. X 1,000. 

 M, F. vasinfectum from cotton-wilt. Four macroconidia. X 1,000. 



