360 PLANT DISEASES 



Wissensch. Anstalten, x., 2, 74 (1893). Asd subclavate, 

 apex mostly rounded, 92-105 //, long, 16-25 /* thick at the 

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

 base about 8 //, wide ; ascospores about 4 ^ diam. 



Taphrina aurea, Fries, Obs. Myc., pt. i. p. 217 (1815). 

 Asci very variable, sometimes slender and deeply sunk 

 in the leaf, 80-112 x 20-2 7 p; others are stouter, rounded 

 below, and entering but little between the epidermal cells, 

 measuring 80 x 30-40 p ; ascospores about 4 p 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. Set. Nat., 1851, 

 vol. xv. p. 1 60, 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 p long. 



Uncinula, Lev. Perithecium 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 



