PLATE 83 

 Colletotrichum circinans and C.fructus: 



A. — Photomicrograph of cross section of naturally infected onion scale. Note 

 that the fungus is confined largely between the cuticle and the subcuticular wall. 

 The epidermal cells and two layers of the parenchyma cells have collapsed, while the 

 uninvaded cells beneath the lesion are slightly enlarged and distended. 



B. — Photomicrograph of cross section of an infected onion scale held for several 

 months in poorly ventilated storage. Note that the stroma is excessively developed 

 and that the cuticle is still intact except where ruptured by the acervuli. 



C, D. — Photomicrographs of cross sections of C. circinans (C) and C.fructus (D) on 

 apple fruit. Note similarity between the two forms and the subcuticular origin of the 

 stromata in each case. 



