28 Bulletin 313 



MiCROSPH^RA ALNi (Wal.) Wiiit. - — On leaves of lilac, alders, 

 oaks and many other plants. Producing persistent or non-persistent 

 mycelium. Perithecium scattered or grouped, and variable in size, 

 66-110 fx, occasionally 135 fx. Appendages irregular, 3-6 times di- 

 chotomously branched, tips of final branches recurved. Asci 3-8, 

 ovate or ovate-globose, 42-70 x 32-50 fi, usually with short stalks; 

 4-8 spores, 18-23 x 10-12 fi. 



101. Perithecium, 1/6. 102. Tips of appendages, 1/12. 103. Immature as- 

 cus and spores, 1/12. 104. Mature ascus, 1/12. 105. Ascospores, 1/12. 



Phyllactinia corylea (Pers.) Karst. — On the leaves of oaks, 

 alders, and many other plants. Produces evanescent, sometimes 

 persistent mycelium on the under and sometimes on the upper sur- 

 face of the leaves. Perithecia scattered or grouped, 140-270 fi, 

 rarely 350 fi; appendages 5-18, equatorial. Asci 5-45, subcylindrical 

 to ovate-oblong, 60-105 x 25-40 /x; more or less stalked, 2, rarely 3 

 spores, 30-42 x 16-25 /i. 



106. Perithecium, 2/3. 107. Appendage 1/6. 108. Ascus, 1/12. 



