386 



SCIENCE 



[N. S. Vol. LIV. No. 1399 



mixed and poured into the sterile culture dish 

 containing the remaining part of the kernel. 

 (These methods were used extensively by 

 the senior writer in his studies on fungi in- 

 ternal of flax, 1901-1904, and wheat, 1909.) 

 In this manner a greater distribution of the 

 mycelium or spores is possible and allows for 

 accurate interpretation in instances where 

 more than one fungus is being carried. 



In most of the cultural plate work a 

 dextrose peptone agar of the following com- 

 position was used: — tap water 1000 c.c, 

 dextrose 10 grams, peptone 1 gram, agar 15 

 grams. Twenty cubic centimeters of medium 

 were used in all cultural plates in which ten 

 kernels of corn were placed for germination. 



A careful study of the anatomy of seed 

 which showed heavy infection after a steriliz- 

 ing treatment, readily indicated how these 

 parasitic fungi were escaping the disin- 

 fectant. In most cases where the internal 



pathogenes were not inhibiting germination, 

 the fungi had gained entrance only to the 

 cavity under the " cap " ; or had penetrated 

 but short distances under the pericarp. This 

 was true of each of the fungi Cephalosporium 

 sacchari, Gibheirella sauhinetii, Fusarium mo- 

 niliforme and Diplodia zeoB. Whenever any 

 of these pathogenes became established in the 

 tissue comprizing the embryo the vitality was 

 either destroyed or greatly inhibited. Ob- 

 servations thus far made indicate as a result 

 of cultural and germinator tests that in 

 order of importance of inhibiting germination 

 Diplodia z&w stands first, followed in order 

 by Gibherella sauhinetii, Fusarium monili- 

 forme and Cephalosporium sacchari. 



The samples submitted for this survey from 

 states other than Delaware were not neces- 

 sarily representative. The studies show at 

 least the general occurrence of these fungi. 



The establishment of C. sacchari as a para- 



DISTEIBTJTION AND PREVALENCE OF PAEASITIC FUNGI INTERNAL OF SEED CORN 



1 All data reported in terms of per cent. 



