io8 DISEASES OF THE SWEET PEA 



or fruit bodies in about two weeks after 

 sowing. These perithecia are covered 

 with dark hair-like appendages. The 

 hairs are straight or coiled at the apex 

 and septate at unequal intervals, and cov- 

 ered with very minute pointed warts (fig. 

 10^). The asci are very evanescent and 

 can only be seen in very young cultures 

 just as the perithecia are forming. In old 

 cultures the ascus wall is easily ruptured 

 so that it is difficult to make out the ar- 

 rangement of the ascospores within. 

 There are eight ascospores in each ascus 

 (fig. IOC and d) . The ascospore is apicu- 

 late (fig. 10^) at both ends. Its wall is 

 smooth, light brown when young and dark 

 when old. It will germinate readily 

 in distilled water or in any nutrient 

 broth. 



Chaetomium root rot is not likely to 

 prove troublesome in greenhouses where 



