THE FUNGI WHICH CAUSE PLANT DISEASE 567 



Myceliophthora Costant (p. 566) 



Sterile hyphse creeping, simple or somewhat branched, bearing 

 conidia at the apex; conidia solitary, 

 acrogenous, ovoid. ^^^ 



A single species M. lutea Costant. " 

 causes disease of cultivated mush- 

 rooms in France."' ,^— ,, 



Ophiocladium Cavara (p. 566) '"^^I^^^'C^ 



Fertile hyphse fasciculate, tor- G -vC 



tuose; conidia acrogenous, ellip- Fia.381. — O. hordei accrvulus and 

 J.. spores. After Cavara. 



Two species of which one, O. hordei Cav., parasitizes barley. 



Oosporeae (p. 565) 

 Hyphse short or obsolete, conidia in chains. 



Key to Genera or Oospores 



Conidial chains arising in the hyphse 



Conidial branches simple, arcuate 1. Malbranchea. 



Conidial branches dichotomous, not 



arcuate 2. Glycophila. 



Conidial chains arising at the apex of the 

 hyphse 

 Conidia globose, elliptic, or ovate 

 Conidia all of equal size 

 Sterile hyphse very short or none. . . 3. OSspora, p. 568. 

 Sterile hyphse evident, rarely none 

 Conidia not connected by an 

 isthmus 

 Growing within the substratum 



Haustoria none 4. Monilia, p. 568. 



Haustoria present 5. Oidiopsis. 



Growing on the siuf ace of living 



plants 6. Oidium, p. 569. 



Conidia connected by an isthmus. 7. Pspalopsis. 



Apical conidium larger 8. Halobyssus. 



Conidia fusoid, acute at each end 9. Fusidium, p. 568. 



