728 



Journal of Agricultural Research 



Vol. XX, No. 9 



individual variations exhibited, yet it was soon determined that many 

 of the strains had the same mode for their spore lengths. Therefore, the 

 cultures were classified in regard to the modal length of the spores (see 

 Table III). The strains varied in their modal spore length from 12 to 

 20 /*. Most of the strains have their mode at 1 5 ju. 



Table III.— Mode of the spore length of different cultures of Colletotrichum gloeosporioides 



Microns 



6 7 & 9 10 II IS 13 14 16 16 17 18 19 20 21 22 23 24 25 26 



#rz__z 



zt%^zxt-v-Z^ 



XI I X V \ / 



40 



235 



t 



g30 



o> 





 &20 



Id 

 CD 



Z 15 



D 



Fig. i.— Variability of strains of Colleloirkhum gloeosporioides in spore length. 



It was soon observed that this classification could not be correlated 

 with the classification of the strains based on their cultural characteris- 

 tics. It was hoped that it would be possible to find morphological 

 differences correlated with the cultural characters, but this was not the 

 case. 



In order to show the variability within the strain and the differences 

 between the strains, graphs were made representing the variability in 

 four strains (fig. i). Strain 296 has its modal spore length at 12 /jl, 507 



