174 A Monograph of the Erysiphaceae ^ 



f 



+■ 



Peritliecia 80-140 fi (very rarely 100-175); asci 4-25 (very rarely as many as 36). 

 usually 10-15, 5S-9^ H- ^ong ; spores 20-28 /j. long, averaging 34 X ^4 /"• 7- 



V i 



7. Haustoria lobed. 

 Haustoria not lobed. 



3. galeopsidis. 

 2 . dc/i or a cea ru m . 



8. Perithecia 65-lSo /i in diameter, usually about 90 y. ; asci usually few, 2-8, rarely 



as many as 22, 46-72 (rarely So) /i long. 9. 



Perithecia larger, 130-2S0 [l in diameter, averaging 180-200 ^ ; asci 9-42, 70- 



115 ii long. 10. 



9. Appendages very long, 10-20 times the diameter of the perithecium, assurgent and 



fasciculate. 5. tortilis. 



Appendages long or short, spreading horizontally, often interwoven with the my- 

 celium., 1. polygoni. 



10. Perithecia more or less immersed in the lanuginose persistent mycelium. 



4. graminis. 

 Perithecia not immersed in a lanuginose persistent mycelium. 11. 



11. Spores 4-6, 20-22 X 10-12 u. I. polygoni, var. sepulta. 

 Spores 8, rarely 6 or 7, somewhat roundish, 16-20 X 10-15 y.. 7. aggregata. 



I. Erysiphe polygoni DC. [Figs. 132-139, 143, 155, 158] 



Miicot 



1774- 



Sdcrotmm Bysiphe Pers. Obs. Myc. I : 13 (partim). 1796; 

 Pers. Syn. Meth. Fung. 124 (partim). 1801. 



6". Erysiphe, var. hcrbanuii Alb. & Schwein. Consp. Fung. 

 Lusat. "j^. 1805. 



polyg, 



1805. 



E. convolvuU DC. Fl. Fr. 2 : 274. 1805. 



E. pisi DC. Fl. Fr. 2 : 274. 1805 ; Grev. Scot. Crypt. Fl. 3 : 

 //. /J/. 1825. 



E. heraclci DC. Syn. PI. Fl. Gall. 57. 1806. 



E. aquilegiae DC. Fl. Fr. 6 : 105. 181 5. 



E.scandicis DC. Fl. Fr. 6 : 107. 181 5. 



E. varium Fr. Qbs. Myc. i : 206 (partim). 1815 ; and 2 : 366. 



1818. 



Crypt. Erlang. 329. 1817. 



E. macropus Mart. Fl. Crypt. Erlang. 329. 18 17 



Alphitomorpha communis Wallr. Berl. Ges. Nat. Freund. Verh. 

 1:31 (excl. vars. gramincarmn, labiatanun, cichoraccanuii). I S 1 9; 

 Wallr. Fl. Crypt. Germ. 2 : 758 (partim). 1833. 



A. urticae\^^\\x. Ann. Wett. Ges. 4: 238. 18 19. 



A. trifoliorum Wallr. Ann. Wett. Ges. 4: 238. 1819. 



Wall 



1 8 19. 



