CLAD08P0RIUM. 509 



Cladosporium herbarum (Pers.). This species is found every- 

 where on de;ul ]>lant leniaiiis, but it is also common on living- 

 leaves of many plants. The first suggestion that this form 

 might occur as a parasite came from Haberlandt ^ and Frank." 

 It possesses a dirty-grey, thick, septate mycelium, which may 

 be colourless when young or growing inside a substratum ; it 

 applies itself closely to the surface of plants and even pene- 

 trates through the storaata or cell-walls into the tissues. The 

 conidiophores are erect, otherwise variable in form ; they give 

 oft' conidia from the apex or from lateral processes. The 

 conidia are oval and contain a variable number of cells. Organs 

 of plants attacked show grey spots, and withered parts if they 

 are still alive. 



The following are some of the papers describing Cladosporium 

 herbarum as, in certain circumstances, a parasite. Prillieux and 

 Delacroix,^ on apple-trees and raspberry-bushes ; Cavara,"* on 

 raspberry, cycads, agave, and other plants : Sorauer,^ on peas. 

 Lopriore^ describes this fungus as the cause of a "black" 

 disease on ears of wheat ; the results of infection were however 

 somewhat variable. 



Pdtzema Bos reports it as producing disease, and in some 

 cases death, in fields of oats. Kosmahl and Nobbe ^ found 

 that seedlings of Pinus rigida blackened and died suddenly in 

 the beginning of May, apparently from the attacks of this 

 fungus. Janczewski " states that this Cladofiporiiim is a conidial 

 form of Sphaerella Tidasnei, a new species of Ascomycete 

 estal)lislied liy him.^ 



CI. elegans I'enz. This causes on the orange a disease or 

 "scab," which has been injurious both in Southern Europe and 

 the Southern States of America.^ It attacks chiefly wild orange 



^ Frilhling's landwirth. Zeitunt/, 1878. 



^Die Kratdheiten der PJlanzen, 2ikI Edit., 1896, ii., p. -IWl. 



'* Bulletin de la soc. mt/coloij. de France, vii. 



^ Revue vii/colo'/ique, 1891. 



^ Handhuch d. Pflauzenkrankheiten, 1886. 



'' Berichle d. deutMch. hotan. Gesell, 189-2; Landwir/h. Jahrlnuh, 1894. 



"^ Extraits du Bulletin de VAcademie des sci. de Cracovie, 1892, 1893, 1894. 



* Schostakowitsch (Flora, 1895 (ergzbd.) distinguishes Cladosporium from other 

 genera. 



^Scribner, Bulletin of Torrey Cluh, xni., 1886, p. 181. Underwood, Journal of 

 Mycolorjy, vii., p. .S4. Swingle and Webber, "Diseases of Citrous Fruits," 

 U.S.A. Dept. of A<jrirHlhire Bulletin 8, 1896. 



