ASCOMYCETES 361 



coloured ; asci ovate, pedicellate ; spores 4-6, elliptical, 

 ends rounded, 20x8-10 /j,. 



Oidium stage ( = Oidium tuckeri). 



Phyllactinia, Ldv. — Perithecia globoso-depressed, con- 

 taining many asci, large, appendiculate, seated on arach- 

 noid mycelium ; asci 2-4-spored ; appendages acicular, 

 straight, radiating, base inflated into a vesicle. 



Phyllactinia suffulta, Sacc, Mich., ii. p. 50. — Amphi- 

 genous or often most abundant on the under surface of 

 leaves, cobweblike, often evanescent ; perithecia scattered, 

 hemispherical, at length depressed, large ; asci 4-20, ovate, 

 pedicellate, 8g X 50 /x, 2, seldom 3-4, spored, spores ovate, 

 variable in size, 40-52 x 22-25 ^• 



f, ctraLea. 



Spnaerotheca, Lev. — Perithecia containing one ascus 

 only ; ascus subglobose, octosporous ; spores eUiptical, 

 continuous, hyaline ; appendages of the perithecium 

 filamentous, tips not branched, mixed with the mycelium. 



Sphaerotheca pannosa, L^v., Attn. Sd.Nat, 1851, vol. xv. 

 p. 138, pi. 6, f. 8. — Mycelium cottony then densely felted, 

 white, then tinged ochraceous, persistent ; perithecia 

 minute, globose, scattered ; appendages, floccose, hyaline, 

 short; asci subglobose; spores 8, elliptical, 22-25 X 

 13-16 fj,. 



Conidia in chains, terminal one the oldest, elliptical, 

 hyahne, 20-30 X 13-16 /*. 



Sphaerotheca castagnei. Lev., Ann. Sci. Nat, 185 1, 

 vol. XV. p. 139, pi. 6, f. 9, 10. — Forming a white, cobweb- 

 like, often evanescent mycelium on both surfaces of leaves 

 or on inflorescence ; perithecia scattered, spherical, minute; 

 appendages numerous, short, brownish appendages with 



