MOULDS REFERRED BY AUTHORS TO FUMAGO. 245 



great part of strata of the common Cladosporium herbarum, 

 or possibly of one or more distinct species, mixed up with 

 species of Mystrosporiitm, Triposporium, &c., but seldom in a 

 very perfect state. The Cladosporium is commonly developed 

 on a dusty coat of honey-dew, and affords a convenient matrix for 

 the growth of other mucedinous fungi. This is the Cladosporium 

 Fumago, Fries and Link, and comprises possibly some species 

 even of Persoon's second section. Fries, however, has erred in 

 including under it all species of that section, contenting himself 

 merely with the remark, " The plant, as it occurs with us, has 

 delicate fibres ; but in the south of Europe, on the leaves of olive, 

 lemon, &c., it forms tliicker spots and fibres." To these we 

 shall have to advert presently. Specimens of Fumago vagans 

 on diflPerent leaves are published by Mougeot and Nestler,* 

 No. 690, in their work on the Cryptogams of the Vosges Moun- 

 tains ; by Klotzsch, No. 68, under the name of Cladosporium, 

 Fumago; and by one of us in the Plantes Cryptogames du Nord 

 de la France, Kos. 360, 361, 510, 601 : but we are not aware 

 that any species of Persoon's second section, Polychceton, has 

 been so published. Under No. 601 of the latter work there is 

 the following remark : — " Le Fumago vagatis, decrit d'une 

 maniere incomplete par Persoon, est peut-etre un etat imparfait 

 de la production que nous avons en occasion d'observer sur les 

 feuilles du Chene et du Noisetier, et qui constitue notre genre 

 Polych.(st07i, dont I'organisation singuliere et bien reconnue 

 sera decrite dans un memoire particulier que nous publierons 

 incessamment." The intention of publication was never put iu 

 execution, though entertained so long ago as 1833, and was 

 revived only by the transmission by the late Mr. Lea from Ohio 

 of a species on the leaves of Uvaria triloba, evidently congeneric 

 "with the plant of Persoon, and which we have reason to believe 

 is (in part) Dematium Fuligo, Schwein., No. 1331, and also 

 Gliotrichum Fuligo, Fr. This is referred by Schweinitz, in his 

 Synopsis of North American Fungi, to Cladosporium Fumago, 

 Lk. ; but it belongs evidently to Persoon's section Polychceton. 

 A specimen exists in Sir AY. J. Hooker's Herbarium, marked by 

 Schweinitz himself Cladosporium Fuligo, but, as it appears to 



* It is given there under the name Fumago foliorum, Pers. in litt. This 

 was two years previous to the publication of ' Mycologia Europaa.' Spi- 

 collesia foliorum, Agardh., Syst. Alg., p. 32, is evidently' the same thing. 

 Chevallier figures, under the name of Torula Fumago, Chev., Fl. Par., vol. i. 

 p. 34, tab. 3, fig. 4 b, a portion possibly of some Antennaria, or of the genus 

 indicated by Persoon in the sectional name Polychaton. The mycelium, 

 however, of Cladosporium herbarum varies greatly on different leaves. Dr. 

 Leveille has kindly communicated a multitude of forms, out of which several 

 plausible species might be made from the difl'erent condition of the base 

 from which the fertile threads are given off. 



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