THE FUNGI WHICH CAUSE PLANT DISEASE 503 



present in wood though extending but sparingly into woody 

 tissue. 



A pycnidial fungus agreeing with S. malorum morphologically 

 has been shown by Shear ^^ to be a conidial form of the ascigerous 

 fungus Melanops (=Botryosphseria), see p. 284. 



S. pseudodiplodia (Man.) G. & M. ^^' «* causes an apple disease 

 in Europe. 



S. mori Berl. parasitizes Morus; 



S. ulmi S. & R. the elm; 



S. magnoliae Magnag. the Magnolia in Italy; 



B. japonicum Miy. rice in Japan." 

 S. vincae S. & W. 



Pycnidia gregarious or scattered, globose, immersed, black, 

 small, 260-300 fi; ostiole papillate, erumpent; conidia ovate, 

 ovate-oblong or subpyriform, 17-28 x 10-14 /i. On Vinca." 



Many other forms are recorded on various hosts but their 

 parasitism is questionable. 



Coniothyrium Corda (p. 501) 



Pycnidia subcortical, erumpent or not, globose or depressed, 

 ostiole papillate, black, leathery to carbonous; spores small, 

 ellipsoid, conidiophore reduced or absent. 



More than one hundred fifty species. 



C. p]rriana (Sacc.) Shel. is common on apple leaf spots but is not 

 regarded as their cause.* 



C. concentiicum (Desm.) Sacc. occurs on Yucca, Dracsena, etc. 



C. tumefaciens Gus.*" is described as the cause of a rose canker. 



C. melastorum (Berk.) Sacc.** is on sugar cane. 



C. fuckelii Sacc.*^ 



Pycnidia superficial, scattered, dark, 180-200 /x, globose- 

 depressed; conidia numerous, globose to short-elliptic, 2.4-5 x 

 2-3.5 fi. 



The European form is reported on dead and dying branches and 

 a form closely allied to it, probably identical, has been studied in 

 New York as the cause of a raspberry cane-blight. This fungus 

 and no other was present and typical disease followed inoculation. 

 The organism was recovered in pure culture. Both new and old 

 canes died within two months after inoculation. 



