THE FUNGI WHICH CAUSE PLANT DISEASE 585 



in diameter, numerous, minute, elliptic oblong, 3.3-3.4 x 1-1.5 /x, 

 hyaline. 



It causes a wilt of ginseng. The vascular bundles are yellowed 

 and the ducts plugged by the 

 mycelium. Entrance is apparently 

 through the leaf scars. The fungus J f / Nk P 

 was isolated by Van Hook'^^^ and 

 cultural studies made. In a later 

 article Rankin 2°' has discussed what 

 appears to be this fungus under the 

 name A. panax. 



A. vilmorinii Gue.*"**- ''^^ causes a 

 disease of China asters and a species 

 closely related, one of cacao fruits. 



Spicaria Harz (p. 584) 



Hyphae creeping; conidiophores 

 erect, much branched; conidia apical, fig. 391.— Spore-bearing stalks of 

 catenulate, ovate or elongate, hyaline Acrostaiagmus aibus. The 



' o I J "" spores are borne m heads and are 



or dilute colored. held together at first by a coat 



A , , , . of slime. After Van Hook. 



About ten species. 



S. solani Hart, is said to produce effects on the potato much 

 like those of Fusarium solani. *^^ 



S. colorans v. Hall, the cause of cacao cankers is probably a 

 conidial stage of Calonectria cremea. See p. 205. 



Moniliaceae-Didjrmosporese (p. 565) 



Conidia hyaline, or bright colored, 1-septate, ovoid oblong or 

 short f usoid. 



Key to Genesa of Moniliaceae-Didymosporese. 



Conidia not in chains 

 Saprophytic or on fungi 

 Conidia smooth 

 Fertile hyphse simple or nearly so 

 Hyphae inflated at apex or joints 

 Hyphse denticulate, inflated at 



apex; conidia fusoid 1. Diplorhinotrichum. 



