STUDIES OF DISEASE PRODUCING SPECIES OF FUSARIUM. 227 



plates gives the basis for the statement that Fusarium spores 

 germinate very readily when they are placed under favorable 

 conditions for growth. Frequently, in cultures where there is a 

 large amount of moisture present, spores germinate soon after 

 they are produced. 



Spores of F I from apple, taken from a culture three weeks 

 old on turnip cylinder, were placed in a number of hanging 

 drops of a decoction of apple wood at 4 P. M. The next day at 

 8 A. ]\I. nearly all of the spores had germinated and in some 

 cases the germ tube had branched. Other cultures were made 

 in the same way at 9 A. AI. and when these were examined at 

 4.30 P. AI. all stages of germination were found. In some 

 spores, the germ tubes grow out from the end cells in the direc- 

 tion of the long axis. In other cases, the germ tubes grow from 

 the sides of other cells, the end cells being empty of contents. 

 Fusions frequently take place between the germinating spores 

 as shown in Fig. 94. 



Spores of F II from apple taken from a bean pod culture 

 three weeks old were sown in hanging drops of apple wood 

 decoction at 10.30 A. AI. At 2.30 P. M. the greater part of 

 these spores had germinated. The next day at 2 P. M. con- 

 siderable mycelium had developed and many spores were being 

 formed. Most of these were of the long septate type but some 

 obovate spores were seen. 



Spores of F III from apple were sown in hanging drops at 

 9.15 A. M. At 4 P. "Si. many of these spores had germinated. 

 As a rule the germ tubes grew out from the end cells in the 

 direction of the long axis of the spores but in some cases the 

 germ tubes developed from the sides of other cells. 



Spores of F IV from apple, a fungus identical with F II, 

 were taken from an agar plate culture and sown in hanging 

 drops of 2 per cent saccharose broth where they began to germi- 

 nate in 4 to 5 hours. The large septate spores germinate in 

 the same ways that have been described for spores of the other 

 species from apple. The small non-septate spores germinate 

 after a little longer time than the large septate ones. They may 

 or may not become septate before germination. The mycelium 

 developed rapidly so that at the end of 24 hours a branched 

 growth had formed from a single spore. After two days 



