73 2 



Journal of Agricultural Research 



Vol. XX, No. 9 



cultures in which the mutations occurred had greenish gray, fluffy, aerial 

 growth. None of the cultures showed any variation from the descrip- 

 tion given in the table. This seems to indicate that the cultures were all 

 pure. 



Table V. — Differences in spore size of Colletotrichum gloeosporioides induced by various 



media 



STRAIN 295 



STRAIN 296 



Corn meal agar . . 

 Green bean plug 



Potato agar 



Lactose agar 



Oat agar 



I. 65 ±0. 079 

 I. 71 ± . 082 

 1. 75± .083 



i-53± -°73 

 1. i6± .055 



5. 48 ±0.052 



4. 2 ± . 065 



5-3 ± -°3 

 4v4^± -04 



5. 23± .127 



77 ±0.037 

 97 ± • 046 

 44 ± . 02 1 

 61 ± . 029 

 88 ± .090 



Corn meal agar . . 

 Green bean plug 



Potato agar 



Lactose agar 



Oat agar 



3. 34±o. 056 



4. 68 ± . 014 



4. 56± . 0188 

 4- 54± • 061 



5. 56 ± .064 



o. 836 ± o. 040 

 . 21 ± . 010 

 . 28 ± .013 

 .91 ± .043 

 • 95 ± -°45 



STRAIN 429 



Corn meal agar . . 

 Green bean plug 



Potato agar 



Lactose agar 



Oat agar 



13.03 ±0. 138 



14-75 ± -°95 



13.07 ± . 125 



12. 75 ± . 101 



13. 76 ± . 123 



3-94±o. 036 

 3. 26± . 077 

 3. 99± . 122 



3. 75 ± .047 



4. 58± . 121 



0. 53 ±0.025 



1. 15 ± .055 

 1. 81 ± . 086 



•7° ± -°33 

 1.80 ± .086 



STRAIN 651 



Corn meal agar . . 

 Green bean plug 



Potato agar 



Lactose agar 



Oat agar 



14.43 ±0.115 



17. 23 ± . no 



15. 11 ± .115 



15. 67 ± . 121 



15.06 ± . 113 



4. 49 ±0.013 



4- 5 2 ± -°35 



5. I2± . OI7 



4. 44± .042 

 5 . 3 8± .028 



o. 19 ±0. 009 



± .025 

 ± . 012 

 ± .030 

 ± . 020 



In the fall of 191 7, after the strains had been grown on aitificial media 

 for a year, they were again grown in plate cultures. In a few of the 

 strains there appeared some mycelial growth which differed in color from 



