— 179 — 



the surface of the culture-drop conidia, like those already des- 

 cribed and figured as the summer conidia. 



Fig. 8.— An ascus, with spores germinating within. 



Asci within the perithecium were now examined and the spores 

 were found to be germinating, not only within the asci, but while 

 the asci were in the perithecium, and the mycelial filaments thus 

 produced were crowding out through the ostiolum, (Fig. 9.) 



The interesting discov- 

 ery of the production of 

 conidia directly from the 

 ascosporic mycelium, im- 

 mediately suggested the 

 idea that the ascospore 

 did not ordinarily direct- 

 ly infect the host-plant, 

 but accomplished this 

 only through the conidia 

 it produced. Ascospores 

 were then sown upon the 

 leaves of rapidl3'-growing 

 plants and in four days 

 the mycelium was ob- 

 served ramifying over 

 the epidermis, but in no 

 case could it be found 

 penetrating it. Further- 

 more none of the plants 

 on which ascospores were 



Fig. 9. — A. perithecium removed from the leaf and cQwn became SDOtted 

 showing the projecting filaments from the germinating . . ' 



ascospores. With a Single cxceptiou, 



and this was proven to have been diseased before the ascospores 



