282 



Journal of Agricultural Research 



Vol. XX, No. 4 



Table I. — Appearance of vascular tissue and origin of cultures 



OBSCURE DISEASE GROUP 



HEALTHY GROUP 



4CLO 



5 PC 



6PW 



7PSW... 



8PMe 



9RW 



10RWC0II. 

 11CRC. 



12AEO.. . 



13 EO 



14M 



15DPW... 

 16DPC... 



17 RMc ... 



18 DRW.. 

 19DRC... 



Total 



PARASITIC DISEASE GROUP 



ISOLATION AND IDENTIFICATION OF FUNGI 



Isolations were made by transferring a small piece of tissue removed 

 under aseptic conditions from the region of discoloration directly to a 

 test tube containing sterilized nutrient material prepared in the usual 

 way. Melilotus stems, potato cylinders, and steamed rice were used, 

 the number of each diminishing in the order named. Identifications 

 were made direct from the original tube in some cases, while subcultures 

 were resorted to in others. Except in part of the Fusarium cultures, no 

 attempt was made to identify the species. Two hundred and ninety- 

 one out of the 718 cultures of Fusarium secured were identified as F. 

 discolor var. sulphureum or F. oxysporum, but it is not to be supposed 

 that the remaining 499 cultures were all of other species. Indeed, it is 

 probable that F. oxysporum and F. radicicola predominated among the 

 cultures reported as Fusarium spp. The summarized results of the cul- 

 tural studies are presented in Table II. Two columns of figures appear 

 under each genus reported. In the first column is given the number of 

 instances when the culture was either pure or so nearly so as not to give 



