THE FUNGI WHICH CAUSE PLANT DISEASE 619 



pitose, flexuose, brown, few septate, 70-80 x 5 /t; conidia bro'wn, 

 multiseptate, clavate, 200-225 x 21-26 ix. 



It causes leaf spots on turnips, horse radish and other crucifers. 



M. brassicse Berk. 



Mycelium inconspicuous, conidia clavate, antennaeform, 5 to 

 11-septate, 50-60 x 12-14 /x. 



It is a common cause of black mold on cabbage, coUards and 

 other crucifers. 



M. ramulosum Sacc. is on celery. 



M. catalpae E. & M. «* 



On brownish spots; conidiophores brown, curved, nodose, 8 to 

 12-septate, erect, amphigenous, 90-135 x 6 /x; conidia brown, 

 obovate to pyriform, submuriform, 27-54 x 15-27 n. 



Producing leaf spots on Catalpa in company with Phyllosticta 

 catalpse. 



M. nobile Vize. is on Dianthus. 



M. iridis C. and E. and M. aductum Mas. are on iris; 



M. cheiranthi (Lib.) Fr. on Cheiranthus. 



M. tabacinum E. & E.^" causes thin, white amphigenous spots, 

 2-3 mm. with a narrow dark border; conidiophores effused, 35-45 x 

 3-4 n, septate and torulose above; conidia obovate, 15-25 x 10- 

 12 n, sessile or short stipitate, usually 3-septate. 



It is reported to cause white leaf spots on tobacco. 



M. longipes E. & E. 



On concentric, rusty brown, amphigenous spots, 3 to 5 mm. in 

 diameter; conidiophores effused, amphigenous, slender, 40-70 x 

 3-4 II, septate, often contracted at the septa, erect and more or 

 less torulose above; conidia clavate, 40-50 x 15-20 n, 3 to 

 7-septate, attenuate below into a distinct stipe. On tobacco. 



M. sarciniforme Cav. is reported by Walkoff ^'^^ on red clover 

 in Germany where it causes the leaves to dry and die. 



M. nigricanthium Atk.^^^ 



Amphigenous; condiophores subfasciculate or scattered nodose, 

 septate, olive-brown, 50-140 x 6-7 y,; conidia olive-brown, con- 

 stricted about the middle, rostrate at one side of the apex, 18- 

 22 X 36-50 II. On cotton. 



M. cucumerinum E. & E.»23.324 



Epiphyllous on orbicular, subconfluent, brownish spots, 3-4 



