STUDIES OF GLOMERELLA FROM DIFFERENT HOSTS. 57 



tubes. Acervuli developed in abundance in tubes a and b. The 

 mycelium was white and rather scanty. In tubes c and d the 

 mycelium was much more abundant and darker colored. Chlamy- 

 dospores were also found in these cultures. On October 16 many 

 perithecia were present in tube a but none in b. The difference 

 between these two tubes was striking, though the cultures came 

 originally from the same acervulus. Variations in the size and shape 

 of the asci are shown in Plate III, figures 30 to 34. 



In two cultures out of eight made in August from diseased tissue 

 on small black sunken spots on shoots of a Concord grapevine from 

 Vienna, Va., both acervuli and perithecia of Glomerella were pro- 

 duced. Setse were found in these acervuli. As other organisms pre- 

 dominated in most of the cultures, it is, of course, uncertain whether 

 any of these cankers were primarily due to Glomerella, which has not 

 heretofore been reported as occurring upon grape shoots, so far as 

 known. Setae seemed to occur less frequently in the form from the 

 grape and apple than in those from other hosts. Other cultures from 

 grapes from different parts of Virginia produced an abundance of 

 acervuli, and also in one case numerous peritheciumlike or sclerotoid 

 bodies, which always remained sterile. The asci ranged from 55 to 

 98.5 by 9 to 15 [i. Asci and ascospores are shown in Plate I, figures 

 1, la, 2, and 2a. 



The peri thecial form seems to be the Pliysalospora baccae of Cavara 

 (17). The conidial form has been described by the same author as 

 Gloeosporium pJiysalosporae. 



MISCELLANEOUS. 



In order to compare the behavior of Glomerella from different hosts 

 in pure cultures, tubes were inoculated February 7 with conidia from 

 leaves of the following six hosts which were growing in the greenhouse : 

 Caryota, Costus, Curculigo, Maranta, Persea, and Piper. These cul- 

 tures all made a growth practically identical in appearance, and 

 most of the tubes produced acervuli varying more or less in num- 

 ber and size. The mycelial growth was about equal in all. One 

 tube from Costus and one from Curculigo failed to produce acervuli. 

 The difference in these cultures from different hosts was much less 

 marked than is frequently the case in cultures made from a single 

 acervulus on the same host. 



On January 29 apparently healthy leaves were taken from nine dif- 

 ferent hosts in the greenhouse, as follows : Citrus limonum, Citrus 

 decumana, Citrus nobilis, Eriobotrya japonica, Psidium guajava, Thea 

 japonica, Pitcairnia coraTlina, and Ficus longifolia. The surfaces 

 were thoroughly washed with corrosive sublimate, 1 to 500, and the 

 leaves then placed in sterile moist chambers. On February 15 all the 



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