40 PAKASITES BELONGING TO THE GENUS GLOMEKELLA. 



tinge was visible in all the cultures, and at the end of a week the agar had 

 become a decided pink color, and acervuli were present in all the tubes. 



On November 24 three more plates and three tubes were made from 

 an acervulus on the same apple used in the previous cultures. From 

 the poured plates six transfers of single germinated conidia were 

 made to tubes. 



On November 28 three cultures made by direct transfer from an 

 acervulus on the same apple showed the same pink color observed in 

 all previous cultures from this apple. Acervuli were present. There 

 was no color in the plates at this time, though acervuli were present. 



On November 30 the pink color was very conspicuous in the six 

 single-spore cultures, and the cultures were practically identical in 

 appearance with those in the other tubes. The appearance of the 

 pink color in all the pure single-spore cultures completely dispelled 

 the natural suspicion that the first cultures might have been con- 

 taminated. These cultures, though kept for several months, never 

 developed any dark mycelium, the growth of hyphss being white or 

 only slightly grayish. The cultures differed in this respect from most 

 other cultures from apples and other hosts, which usually produce more 

 or less of a dark greenish or smoky-colored mycelium, especially 

 when old. Chlamydospores were present in these cultures, but 

 differed slightly from the usual form, many being large and regular. 

 In the following June transfers were made from these old cultures, 

 which were still living, to slant agar tubes. The growth was very slow. 

 On September 4 conidia were present, and the agar showed a slight 

 pinkish color. One tube showed little or no color. Other transfers 

 from a tube showing color made a more abundant growth of acervuli 

 and showed more of the pinkish color. 



On December 4 two sound apples were inoculated by puncture, 

 using conidia from one of the single-spore cultures from this chromo- 

 genic form. The surface of the apples was carefully sterilized by 

 washing as usual, after which they were placed in a sterile moist 

 chamber. Decay began at the points of inoculation in a few days, 

 and on December 17 the decayed areas on both of the apples were 

 more than an inch in diameter and slight pustules, apparently young 

 acervuli, were developing on the skin. On December 26 acervuli 

 having all the characteristics of Glomerella were numerous on the 

 decayed spots. The conidia were extremely variable. No setae 

 were found. 



On January 4 and 5 plates were poured, using conidia from one of 

 the inoculated apples just described. Four transfers were made of 

 single germinating spores to tubes of agar. The general appearance 

 and development of the fungus in these tubes was very similar to that 

 in the previous cultures of this chromogenic form. One culture failed 

 to grow; the other three soon began to show the pink color in the 



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