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Mycologia 



of this fungus in PL Crypt. France Ser. I, No. 1625 shows that 

 there is a single cavity in the pycnidium as he stated and that 

 there is no stroma, hence it could not be correctly referred to 

 Centhospora whose type is C. phacidioides, which has a clypeate 

 stroma enclosing several distinct pycnidia. However, like so 

 many genera this was poorly defined and contained a group of 

 very diverse species not congeneric. Desmazieres' fungus proves 

 to be identical with the pycnidial form of Pezizella lythri found 

 on Rosa, Rubus and other hosts. Smce this is the oldest specific 

 name yet known to have been applied to the pycnidial form, it 

 may be called Sclerotiopsis concava (Desm.) n. comb. The pyc- 

 nidial form of Pezizella lythri is referred to the form genus Sclero- 

 tiopsis of Spegazzini (1882) because it is identical with his mono- 

 type of the genus, 5". aiistralasica, as shown by careful study of an 

 authentic specimen of Spegazzini's species preserved in the her- 

 barium of the New York Botanical Garden. Diedicke (1911) 

 basing his interpretation of this genus apparently on that of 

 Allescher (1901) and on 5\ cheiri described by Oudemans, and 

 other forms previously referred to Phoma, revises the original 

 diagnosis and includes several species with multilocular stromata 

 clearly not congeneric with Spegazzini's type. V. Hohnel (1914) 

 has already pointed out Diedicke's error in the interpretation of 

 Sclerotiopsis. The latter 's mistake might perhaps have been 

 avoided if the type method of applying generic names had 

 been followed and the application of Spegazzini's genus re- 

 stricted to species congeneric with his monotype, S. aiistralasica. 

 Of course even then one might have such broad views of generic- 

 limits as to include forms having large multilocular stromata; but 

 it seems best to the writers to keep such forms separate until more 

 is known about the constancy and taxonomic value of such char- 

 acters and the life histories of the organisms. On a basis of a 

 comparison of morphological characters, one might be justified in 

 regarding Pilidium Kunze (1823) as a synonym of Sclerotiopsis 

 and in substituting Kunze's name for this pycnidial form. The 

 monotype of Kunze's genus, P. acerinum Kze. (not Leptothyrium 

 acerinum attributed to (Kunze) Cda. as found in some exsiccati, 

 e.g., D. Sacc. Myc. Ital. Nos. 762 and 974) is almost if not quite 



