117 



species that apiK-ar to be new to science were exhibited, together 

 with photographs and detailed sketches of microscopic structure. 

 It is expected that the paper will soon be published. 



Mr. C. W. Knimons of Columbia University followed with an 

 account of "The Cytology of Cicinnobolus Ccsatii DeBary." Ci- 

 cinnobolus Ccsatii DeBary is one of the Fungi Imperfecti falling 

 in the form family Sphaeropsideae, but presumably an Ascomycete 

 and of si)ecial interest since it is parasitic on another Ascomycete. 

 It is an intracellular parasite of the Powdery mildews, growing 

 inside the hyphae of the latter and transforming mycelial hyphae, 

 conidiophores, and ascocarps of the mildew into pycnidia which 

 bear the spores of Cicinnobolus. It also invades cells and intercel- 

 lular spaces of the host of the mildew. It was found abundantly 

 infesting Erysiphe Cichoracearum on Helianthus Tuherosus and 

 collections were made from a few other hosts. Good fixation was 

 obtained with Flemming's weaker fixatives, and Flemming's triple 

 stain gave characteristic staining reactions. 



The parasite causes a granular degeneration of the host proto- 

 plasm. 



The p}cnidia vary in size and shape according to the organs in 

 which they are built and the stage of development at which invasion 

 occurred. The spores seem to be borne endogenously, nuclear di- 

 visions in the spore mother cell being followed by the pushing out 

 of the cell wall into a projection which is then abstricted as a spore. 

 This suggests spermatium formation, yet these are spores which 

 apparently propagate the fungus. They germinate readily in dis- 

 tilled water and DeBary has observed that they infect hyphae and 

 spores of mildew. 



Late in the season rather thick-walled resting cells are formed 

 in parenchymatous masses on the leaf surface, in the epidermal 

 and trichome cells of the leaf, and in its intercellular spaces. i\Ia- 

 terial collected in the spring shows perithecia imbedded in the dead 

 leaf tissue. These are believed to be the sexual fruit structure of 

 Cicinnobolus. 



The fungus, although known commonly as an intracellular para- 

 site within a fungus which is itself an obligate parasite, grows and 

 fruits on glucose and peptone agar. 



FoRMAN T. IMcLean 

 Secretary 



