96 Journal of Mycology [Vol. 13 



granules into the young- hyphae clear spaces appear. Often the 

 end of the germ tube swells, becomes cut ofif by a wall and rap- 

 idly assumes a dark color and, in general, takes on the appear- 

 ance of the black bodies which are so characteristic a feature 

 in the germination of the anthacnoses. As with the anthracnoses 

 this body may remain without further development or it may 

 germinate immediately (Fig. 6). 



There has been much doubt as to the true nature of these 

 structures. Frank^ regarded them as holdfasts to assist in 

 securing penetration into the host. Hasselbring- as the result of 

 recent investigation regards them in he same light. Other writ- 

 ers have variously considered them as spores, secondary spores, 

 buds, gemmae chlamydospores, etc. References to the literature 

 regarding these bodies is to be found in Hasselbring's article. 



These structures have been described for Colletotrichum 

 and Gleosporium, one of the authors of this paper having studied 

 them in some twenty-five species from these two genera,^ in 

 Polystigma, Fusicladium and V^olutella.* 



Transfers into solidified pea agar and apple agar plates were 

 made under aseptic conditions from the regions immediately be- 

 neath the skin in a diseased spot, also from the diseased tissue 

 near the boundary between diseased and healthy portions, and 

 in every instance pure cultures of the fungus were obtained. 

 Pure cultures were also obtained by plating from water contain- 

 ing the spores of the fungus. 



Grown upon plain agar or pea agar the mycelium was hya- 

 line with many black tubercles ; on agar containing carbohydrates 

 as starch or sugar the mycelium was densely black. 



In none of the cultures upon artificial media were spores 

 formed. On sterilized apple twigs, however, spores were formed 

 in great abundance. The mycelium on this medium was at most 

 only slightly fuscous and was in most cases hyaline. 



Inoculations were made from mycelium grown in pure cul- 

 tures by pricking the skin of an apple and laying on, or insert- 

 ing, a bit of the mycelium. Within a few days a well developed 

 spot was obtained. 



Many attempts were made to secure inoculations through 

 unbroken cuticle but in no instance with success. It is evident 

 that a bruise or break of some kind is necessary. This evidence 

 correlates well with the fact that the disease, as is true of so 

 many fruit diseases, is much more conmion at the blossom end, 



' Ueber einjge neue und weniger bekannte Pflanzenkrankheiten. 

 Ber. Deut. Bot. Ges. 1:29-34, 58-63. 1883. 



^ The Appressoria of the Anthacno.ses Bot. Gaz. 42, 135. 



' See article by Halsted : The Secondary Spore in Anthracnoses, 

 N. J., Agr. Experiment Station Report. 1802, 203. 



* Stoneman, A Comparative Study of Some Anthracnoses, Bot. Gaz. 

 2G:G9, 1898. Plate 13, fig. 82 and Plate 14, fig. 86. 



