316 



STATE HORTICULTURAL SOCIETY. 



on the same day, and c at 11:45 a. m., Dec. 16. The spores are therefore 

 developed with great rapidity under favorable circumstances. In the 

 same culture were other spores which developed a much greater extent of 

 mycelium and number of spores. This group was chosen because of its 

 limited extent, being thus more convenient to sketch. 



During the growth and produc- 

 tion of spores the coarse granules 

 gradually disappear. As the cult- 

 ure ages the mass of spores 

 becomes greater at the center of 

 each group of mycelium. In a 

 few days spore production seems 

 to cease and then long, sterile 

 mycelial threads grow out to a 

 considerable distance. 



At the same time there are 

 usually developed buds or gemmae, 

 at the ends of certain threads. 

 These are colorless at first and 

 may be detected by their irregu- 

 larly oval outline, and greater 

 diameter than the parent thread. 

 They soon acquire a dark brown 

 color, sometimes become septate, 

 or bud into rudimentary sclero- 

 tia. One of these developed 

 quite early in the culture as 

 shown at x, figure 3. 



Spores were also sown on 

 sterilized bean stems. The fun- 

 gus grew readily and produced 

 numerous spores during a few 

 days when the threads assumed a 

 dark brown color and grew in great 

 profusion over the surface of the 

 stems. Frequently the threads 

 associated themselves into strands, 

 or compact wefts of parallel threads several layers deep. Within these wefts 

 and strands were developed numerous bodies suggesting pycnidia or peri- 

 thecia, rotund in form, the interior cells hyaline and with rich protoplas- 

 mic contents, the peripheral cells dark brown in color. 



In some cases these measured 80 to 100*, and frequently the depth of 

 the weft of dark mycelium in which they were seated exceeded this 

 measurement. 



Late upon the surface of this growth free threads arose in a procumbent, 

 assurgent, or nearly erect position. All of this development on the bean 

 stems took place in ten days. This culture is very suggestive of the prob- 

 able development cycle of this Oloeosporium and related forms. It 

 probably presages the development of an ascigerous stage; whether or not 

 that ever actually takes place 'is yet to be determined. The blackening 

 of the stroma in the pustule on the stems of the privet is probably 



* These measarements are in terms of the micromlllimeter. 



