251 MOULDS REFERRED BY AUTHORS TO FUMAGO. 



*** {J\Iicroxipliiuiii) Harv. Peridia simple, subulate. 



11. C. Footii, Berk, and Desm. Maculseforme setulosuin ; 

 peridiis subulatis simplicibus ; mycelio subliyalino subgelatinoso. 

 Fumago Fayi, Pers., Myc. Eur., vol. i. p. 10. Microxiphium 

 Footii, Harv. MSS. 



Extremely common on the leaves of evergreens, when it is 

 often accompanied by Strigida Babingtonii, and also on the 

 leaves of deciduous trees, as the Beech, and even on herbaceous 

 plants, as Mercurialis perennis (Figs. 10 anil 10*). 



Forming little, generally, orbicular thin patches, which under 

 a microscope are setulose. Mycelium subgelatinous, readily 

 imbibing water, subhyaline, when young subcontinuous, when 

 old distinctly moniliform ; the articulations elliptic, with one or 

 two nuclei. Peridia dark, setiform, outer coat hyaline, the 

 threads at first cylindrical, at length moniliform, hyaline, the 

 ultimate joints breaking off; in some states the peridia are quite 

 naked. They frequently, but not universally, spring from a 

 little bulbous base. 



The fruit has not been observed in this species. Its discovery 

 may warrant the formation of the genus Microxiphium, Harv. 

 It is scarcely probable that the asci in so narrow a space should 

 be of the same nature as in the other species. It occurs so fre- 

 quently with Strigula Bahingtonii that it hns been suggested that 

 it bears the same relation to that species tliat Tricharia does to 

 certain epiphyllous lichens. It is, however, found without any 

 trace of the lichen, and the lichen occurs equally free from the 

 bristly threads. In the absence of all information respecting the 

 .sporidia it is impossible to come to any certain conclusion : it is, 

 however, highly probable that both in Tricharia and our present 

 species a great similarity may exist in this respect. The speci- 

 men on 3Iercurialis was at first thought distinct, but there are 

 no sufficient characters to warrant its being kept apart at 

 present. 



We can scarcely suppose that all the species proposed above 

 will be retained. The first and three last are, at any rate, good 

 species ; it is, perhaps, more doubtful whether all the interme- 

 diate species are equally good, though the differences are suffi- 

 ciently striking. Were the fruit of all perfectly known, we 

 might speak more confidently. 



We conclude our memoir witli the notice of a new genu^:, 

 which is abundantly produced in certain situations in South Ca- 

 rolina, though the fructification is of rare occurrence. It is 

 generally, if not always, accompanied by a new species of 

 Myriangium, but has not the slightest connexion with it. The 

 threads are cylindrical, inarticulate, fasciculate, creeping widely 



