Griffiths : Pvrenomvcetes 435 



This species resembles AT, IcucotncJia Cda. very much out- 

 wardly, except that the perithecia are less hairy and the ostiolum 

 less fimbriated. The spores and asci are, however, decidedly differ- 

 ent although about equal in size. Specimens from Rehm's Ascomy- 



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cetes have slightly inequilateral spores with acute hyaline apiculi. 

 I have not been able to find asci wuth mature spores in my speci- 

 mens, but they arc common in the European ones. The illustra- 

 tion of the ascus in this paper was made from one in which the 

 spores were just beginning to change color, because of my in- 



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ability to get the asci with perfectly mature spores out of the 

 perithecia without rupturing them. In fact the asci of this species 

 are much like those of Sordaria airvicolla as regards persistency. 

 I have often found immature asci in perithecia which had a globu- 

 lar mass of mature spores on the ostiolum, showing that there is 



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a succession of development correlated, I judge, with the large size 

 of the fully formed asci as compared with that of the pcritheciurn. 

 Some of the asci become mature, rupture, and allow their spores 

 to escape, thereby giving room for other younger asci to develop. 



Sordaria mixuta FckL 



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 h 



Perithecia superficial, scattered, thin, membranous, white to 

 fuscous, and so transparent that the spore -bearing area which oc- 

 cupies rather less than half the length of the perithecium can be 

 -readily distinguished, covered with short septate agglutinated hairs 

 which arc more prominent around the smooth, black, naked, conical, 

 erect or curved apex, 140-180//. x 360-510//. : asci paraphyseatc, 

 cylindrical, with a contracted stipe one half the length of spore- 

 bearing portion, 4-spored, I 5-18 // X 1 00- 1 \o It ; spores monoseri- 

 ate, elliptical, acutely pointed, oliwaccous to black and opaque when 

 mature, 13—14// x 16-22 //, terminating below in a hyaline straight 

 or slightly curved gelatinous appendage one half the length of the 

 spore. PL j6j,f. 10-12. 



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The asci are without exception 4-spored and uniscriate. Dr. 



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Winter (Die deutschen Sordaricn, Abhand. der Naturforsch. Gesell, 



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zu Halle, 13: 67—107. 1887) characterizes this species as having 

 4- or 8-spored asci. But he also finds in many of his collections 

 and cultures of German specimens that one or the other form is 



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quite constant, while in still other material the two forms are 

 mixed. 



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Dead culms and lea\'es of Poa Nevadensis hax'incr on them 



