36o PLANT DISEASES 



Wissensch. Anstalien, x., 2, 74 (1893). — Asci subclavate, 

 apex mostly rounded, 92-105 fj. long, 16-25 [>. thick at the 

 free part, portion between the epidermal cells 30-50 /u long, 

 base about 8 jU wide ; ascospores about 4 /x diam. 



Taphrina aurea. Fries, Obs. Myc, pt. i. p. 217 (18 15). — 

 Asci very variable, sometimes slender and deeply sunk 

 in the leaf, 80-112 X 20-27 H-! others are stouter, rounded 

 below, and entering but little between the epidermal cells, 

 measuring 80 x 30-40 fi, ; ascospores about 4 ji* diam. 



Perisporiaceae. — Perithecia distinct, not produced on a 

 stroma, coriaceous or subcarbonaceous, not provided with 

 a distinct mouth, hence splitting irregularly to allow of the 

 escape of the asci ; mycelium superficial. 



Microsphaera, Lev. — Perithecia containing many asci; 

 asci ovoid or oblong, 4-8 spored ; appendages branched at 

 the tip. 



Microsphaera grossulariae, Lev., Ann. Sci. Nat., 185 1, 



vol. XV. p. 160, tab. 9, f. 25. — Mycelium cobweblike, 



greyish-white, on both surfaces of leaves ; perithecia 



scattered, 75-120 /*, appendages 10-20, once to twice as 



long as diameter of perithecium, 4-6 times dichotomously 



forked at the tips ; asci 3-5, ovoid ; spores 4-6, variable in 



size, 15-30 /x long. 

 «- turn. 



Uncinula, Lev. — Perithecmm containing several asci, 



which are 2-8-spored ; appendages free from the mycelium, 



curled at the undivided tips. 



Uncinula spiralis, Berk., Crypt. Bot., p. 268, f. 64. — 

 Mycelium arachnoid, amphigenous, often evanescent; 

 perithecia minute, scattered, globose, blackish-brown, 

 appendages 10-20, variable in length, septate, occasionally 

 forked, tips loosely and spirally twisted, basal portion 



