322 FUNGOUS DISEASES OF PLANTS 



directly associated with the roots, the mycelium may be at first almost 

 white and flocculent, later becoming brownish-red. A rhizomor- 

 phic stage is also developed, which is clearly distinguishable from 

 that of Agaricns mcllcns. This may be in contact with the roots, 

 often beneath the bark, but it also provides for the spread of the 

 fungus through*, the soil. It may give rise to a filamentous my- 

 celium in the -soil. According to Hartig tuberculate sclerotia are 

 often produced from the strand beneath the bark or from the gen- 

 eral mycelium upon the dead vines. From the sclerotia as well as 

 from any superficial mycelium there may arise clusters of hyphae 

 (conidiophores) bearing minute, simple, hyaline conidia. Pycnidial 

 and perithecial stages have been described. Hartig was convinced 

 that he had clearly established the parasitism of Dematophora and 

 that it might be considered a fungus of much practical signifi- 

 cance, not only with respect to viticulture, but also important in 

 connection with the fruit interests generally, for the fungus is 

 reported as of serious consequence to fruit orchards throughout 

 southern Europe. Diverse opinions prevail with respect to a per- 

 fect stage of this organism. 



XXVI. ANTHRACNOSE OF BEAN 

 Colhtotrichum Lindemuthianum (Sacc. & Magn.) Scribner 



BEACH, S. A. Bean Anthracnose and its Treatment. N. Y. (Geneva) Agl. 



Exp. Sta. Kept. 11 : 531-552. figs. 1-7. 1892. 

 FULTON, H. R. Bean Diseases. Anthracnose or Pod Spot. La. Agl. Exp. 



Sta. Built. 101: 9-13. 1908. 

 WHETZEL, H. H. Some Diseases of Beans. Cornell Univ. Agl. Exp. St\ 



Built. 239: 198-214. figs. 99-115. 1906. 

 WHETZEL, H. H. Bean Anthracnose. Cornell Univ. Agl. Exp. Sta. Built. 



255: 431-447- figs. 217-222. 1908. 



Distribution and host relations. The bean anthracnose or pod 

 spot ranks with the blight in importance. It is widely distributed 

 throughout the limits of bean culture, and it occurs both upon 

 field and garden varieties. There are probably some differences 

 in the resistance of the various varieties to the attacks of the 

 fungus, but there is as yet no experimental evidence to show 

 that immune varieties exist. It is probable that many of the 

 so-called " rust-proof " sorts indicate merely that the seed were 

 selected, through a generation or two, from fields which showed 



