234 Maine; agriculturai, expe;rime;nt station. 1913. 



ance on this medium, adding to the evidence that these strains 

 belong to one species. All produced a'bout the same amount 

 of white aerial mycelium and all showed some yellow and con- 

 siderable red color when the plate cultures two weeks old were 

 viewed from the under side. 



F. roseum. F XVIII, from wheat made a rapid growth and 

 the Peri dishes were completely filled by the white aerial 

 mycelium when the cultures were 5 days old. Later a small 

 area which showed red color appeared at the center of each 

 plate. A small number of septate spores were found in these 

 cultures. 



The forms from cucumber, F VII and F XIX, squash, F 

 XXIII, and tomato, F XXI and F XXII, produced a rather 

 large amount of white aerial mycelium. The one species from 

 cucumber, F XX, which has been referred to as making less 

 growth than the others on other media did not spread so rapidly 

 in the plates as the others and could easily be distinguished 

 from them. The culture of this fungus is shown in Fig. 104. 

 All of the forms from cucumber produced chlamydospores. 



The Fusarium, F XIV, F XLIV and F XLV, from China 

 aster made a good growth ibut only a small amount of aerial 

 mycelium developed. The color was white throughout. The 

 spores were nearly all of the small one-celled type. 



Prune Agar. The prune agar used in this work was prepared 

 by making a decoction from 6 large prunes for each 1000 c. c. 

 and adding 2 per cent dextrose and 2 per cent agar. It has 

 been found that when too many prunes are used the agar 

 becO'mes soft and that the use of a small enough number of 

 prunes to give a solid agar makes the medium too poor in food 

 for good growth of fungi. It was thought that adding 2 per cent 

 dextrose to the agar containing the decoction from 6 prunes in 

 1000 c. c. would overcome both of these difficulties and the 

 results have been fairly satisfactory. Species of Fusarium 

 grow readily on this agar but do not produce aerial mycelium 

 to such an extent as on synthetic agar. Prune agar is a favor- 

 able medium for the production of red color in those species 

 which are characterized by the development of that color. 



Fusarium forms I, II, and IV from apples spread rapidly 

 over the plates but showed only a small amount of white aerial 



