402 BRITISH DISCOMYCETES. 



No. 2232; Gill., " Champ.," p. 201. Oidium bullatum 

 B. and Br., "Jour. Hort. Soc.," ix. p. 51, with 

 fig. Taphrina bullata Tul., " Ann. Sc. Nat./' ser. 5, 

 vol. v. p. 127; Johanson, "Vet. Ac. HandL," 42, p. 33. 

 Exoasciis bullatus Fckl., " Symb. Myco.," nacht. ii. p. 49 ; 

 Sadebeck, L c. 



Exs. Fckl., "F. Rh.," 2551; Thum., "Fung. Aus," 

 972 and 1056. 



On living pear-leaves. It also occurs on Cratcegus 

 Oxycanthus, and C. monogyna. April and May. 



The asci are 30 37 X S/LL ; the sporidia 4'5ju (Sade- 

 beck, L c.). Asci 15 25 x 10// (Cooke, I. c.). 



Name Bullata, a blister ; blistered. 



Shrewsbury ! 



(b) Asci not furnished ivith a stem-cell. 



4. Ascomyces Potentillce. (Farlow.) 



Decolorizing (to pale yellow-green) the branches and 

 leaves, rendering the branches several times thicker than 

 their natural size ; asci clavate, rounded or truncate at 

 the summit, attenuated below into a slender, non-septate 

 stem, continuous with the mycelium, which spreads 

 through the intercellular spaces of the epidermis ; sporidia 

 8, oblong-elliptic, 5 8 X 4/u. 



Exoascus deformans, var. Potentillce Farlow, " Proc. 

 Am. Ac. A. and S.," xviii. (1883), p. 84. Taphrina 

 TormentillceRosi., "Bot. Tid," ser. 3, vol. iv. (1884- 

 1885), p. 239 ; Johanson, " Vet. Ac. Hand!.," 42 (1885), 

 p. 29, t. 1, f. 2. 



On Potentilla Tormentilla, Scop. 



The asci in the Scottish specimen are truncate or 

 rounded at the summit, and attenuated downwards more 

 or less equally to a slender stem-like base, arising 

 directly from the branching hyphse beneath the cuticle, 

 30 to 50/Li high, 7 to 9/z in the broadest part, and 2/x in 

 the narrowest part. The sporidia are confined to the 

 broad upper half of the ascus, elliptic, and (as I measure 

 them) 45 x 2 2' 



