The Scottish Naturalist. 235 



167. L. litigiosum (Desm.) Sacc. 3385, C. 566, M. 1088 (sub 



Leptostroma litigiosum Desm). 

 On Pteris Aquilina ; Autumn. 

 Forth, Tay, Dee. 

 L. Glechomatis B. & Br. (M. 1090). Sec under Leptostroma). 



XXVII. Piggotia B. & Br. 



Pycnidia flattened, irregular, thin, membranaceous, at first con- 

 cealed under a very thin cuticle, which is often thrown 

 off in stellate fashion ; sporidia oblong or subcylindrical, 

 one-celled, hyaline or yellowish ; basidia terete. 



168. P. astroidea B. & Br. 3387, C. 567, M. 1125. 



On living leaves of Ulmus (Elm). 

 Tweed, Forth, Tay. 



XXVIII. Melasmia Lev. 



Pycnidia immersed in an effused black stroma, on leaves or stems, 

 dimidiate, depressed, remaining closed, or opening by a 

 slit ; sporidia fusoid, one-celled, subhyaline ; basidia 

 various. Melasmia is chiefly made up of spermogonia 

 of species of Rhytisma, and resembles them in aspect. 



*i6o. M. acerina Lev, 3390, C. 568., and forma punctata 

 S. &R.3391, C. 569. 

 On leaves of Acer Pseudo-platan us and of A. campestre, 

 in Summer and Autumn. 



Tweed, Solway, Forth, Clyde, Tay, Argyle, Dee, 

 Moray, Ross. 



The two forms are spermogonia of Bhytisma acerinum, Fr., and 

 of its var. punctatum Fr., respectively. Both are abun- 

 dant on the leaves in autumn and winter ; the asci form 

 in spring ; and the Bhytisma is developed in May. 



*i7o. Rhytisma Empetri B. White, usually occurs in the 

 spermogonium stage in Autumn, and is then to be 

 placed under Melasmia. So far as one can decide from 

 plant a description it may be the same as M. Empetri 

 Magn. (Bericht. Deutsch. bot. Gesellsch. 1886 p. 104), 

 Syll. Fung. Add. 4569); but, in absence of complete 

 acquaintance with the latter, I do not venture to employ 

 this name for the Scotch plant. 

 Tay, Dee, Moray. 



