THE FUNGI WHICH CAUSE PLANT DISEASE 575 



Ket to Genera of Botrytides 



Conidia smooth or scarcely roughened 

 Saprophytic or apparently so, often real 

 parasites 

 Conidia typically pleurogynous 

 Fertile hyphse 2 to several-furcate. . . 1. Haplaria. 

 Fertile hyphas simple or nearly so 



Conidia globose or ellipsoid 2. Acladium. 



Conidia short cylindric 3. Cylindrotrichum. 



Conidia acrogenous or pleurogynous 

 Some intermediate joints of the hy- 

 phse swollen and denticulate, 



conidia-bearing 4. Physospora. 



Intermediate joints equal 

 Conidia-bearing hyphae of two sorts, 



the upright alone denticulate 5. Blastomyces. 



Conidia-bearing hyphse of one sort 



Fertile hjrphae simple or nearly so 



Hyphse not denticulate; 



conidia solitary 



Hyphse forming a crust-like 



stratum 6. Hyphoderma. 



Hyphse loose, cobwebby. . . 7. Acremonium, p. 577. 

 Hyphse denticulate; conidia 

 usually grouped 

 Hyphse everywhere denti- 

 culate, bearing conidia 



only at tip 8. Xenopus. 



Hyphse denticulate or pro- 

 liferous at tip alone 

 Apex denticulate, many- 



spored 9- Rhinotrichum. 



Apex inflated-ampulli- 



form, I-spored 10. Olpitrichum 



Fertile hyphse branched 

 Conidia globose to ovoid 

 Both sterile and fertile 

 hyphse procumbent 

 Sterile hyphse intracellu- 

 lar 11. Hartigiella. 



