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The sclerotia of C. pa spali when roatare are usually globular 

 in shape, 2 to 4 rnm. in dianeter, irregularly roughened, on the surface, 

 and yellowish gray in color; the interior is homogenous in structure and 

 contains a considerahle quantity of oil. Gerrainating sclerotia produce 

 one to several stronata, usually tivo or ttiree, with slender whitish stipes 

 3 to 15 nan. in length and with spheridia about 1 mm in diameter. The 

 ^eridia are roughened over the surface, owing to projecting perithecial 

 necks, and are at first whitish in color, later becoming rather bright 

 yellow, and finally brownish. 



A vertical section of a stromatic head shows numerous flasl?;- 

 shaped peritheoia embedded in the outer part of the head. The neck of 

 each perithecium projects a short distance beyond the surface, thus form- 

 ing small piaiple-like projections. The heads are congpletely covered with 

 peritheoia which are o-^ra.1 in shape and measure by 340 by 119|i. Each 

 perithecium contains nuinerous slender, cylindrical asci, 150 to 17C|i in 

 l^igth. At the outer end of each ascus there is a thiable-lilce lsn«» fitting 

 over the end. The wall of the ascus is so thin that it cannot be dis- 

 tinguished clearly. -^The ascospores are filiform and hyaline, being a 

 little less than Ifi in diameter and 70 to 100|i in length. There are pro- 

 bably eijght spores in an ascus, althou^ not more than seven were counted 

 with certainty. Mature spheridia from sclerotia just gathered from the 

 field, vjhen allowed to dry slightly and then moistened, exude asci very 



freely. 



Flowers of Pasioalum dilatatum inoculated with ascospores by 

 by rubbing stromatic heads against stigmas and spikelets of the grass heads 



