78 Journal op^ the Mitchell Society [Septeinher 



an unusual number (Fig. 17). The conidia were likewise multinu- 

 cleate but none with more than three nuclei have been observed (Fig, 

 15). Whether the nuclei in conidia containing more than one nucleus 

 had arisen by mitosis following abstriction of the conidium from the 

 conidiophore or had migrated into the conidium before it had become 

 separated, could not be determined. It is entirely likely, however, 

 that multinucleate conidia arise from both conditions. 



Germination of Conidia and Growth in Culture. 



The organism causing false anthraenose has been isolated several 

 times in each of the three seasons during which it has been studied. 

 It has been cultivated on plain agar, dextrose agar, and vetch decoc- 

 tion agar, on sterilized vetch stems, steamed vetch seed meal, corn meal 

 and tapioca. On each of these media, the isolated colonies remain 

 small and black and are of the tj^pe shown in Figs. 22 and 23. When 

 the cultures are heavily seeded with conidia, a compact black mycelial 

 crust is formed over the surface. 



The conidia are extremely variable in their method of germina- 

 tion. The most common method is budding in a yeast-like fashion, 

 Figs. 1 and 4, so that the tertiary sporidia may be observed to be 

 still connected seriatim with the parent conidia. These buds arise 

 terminally or more rarely as lateral projections. The conidia may be- 

 come once septate early in germination (Figs. 3 and 5) and may de- 

 velop one or more germ tubes similar to the anthracnoses. 



The cells of the parent conidium may become enlarged and brown 

 walled within 48 hours and develop a rudimentary mycelium. Figs. 6 

 and 11. This mycelium may be so reduced that the original parent 

 cells function both as mycelium and conidiophores, Figs. 6 and 9, 

 in which case new conidia are formed as terminal buds. Quite an 

 extensive, thick, closely septate, brown mj^celium forms in other cases 

 which may remain sterile, bud sparingly from lateral conidiophores. 

 Fig. 10, or produce masses of conidia, Fig. 9. All the types of germina- 

 tion and growth illustrated in Figs. 3, 4, 5, 6, 9, 10 and 11 have been 

 observed in the same vetch decoction agar plate, made by sowing the 

 conidia on the surface of the agar. Conidia taken directly from 

 aeervuli have been found to be budding. In old cultures, abnormal 

 conidia of the types shown in Fig. 7 may occur. 



When the conidia are sown on the leaves of hairy vetch, they will 

 within 48 hours, have become once septate, formed a slender tube 



