CONTRIBUTIONS FROM THE WISLEY LABORATORY. 483 



gedrangt stehend, eiformig, beidendig stumpflich, mit 3-4 Scheiden- 

 wanden, sehr klein," and the habitat as on leaves and sheaths of 

 cereals, and on the leaves of Iris and Gladiolus species. It seems 

 evident that if Wallroth refers to a single fungus it is the Brachy- 

 sporium. There is no record of Heterosporium gracile on Gramineae, 

 whereas Brachysporium gracile is recorded both on this family and on 

 Iris, &c. That it was a species principally affecting grasses is apparent 

 from the fact that Wallroth first mentions grasses so particularly and 

 had previously called the species Helmisporium gramineum. (I have 

 unfortunately been unable to trace the description of this.) It seems 

 apparent that the Iris disease under consideration is not included in 

 Wallroth's description. The point is important, since as both fungi 

 cannot take their specific name from the one description the name 

 would have to be taken for the first species spHt off.* If the species is 

 not included in Wallroth's description, what specific name must be 

 apphed to it ? 



The genus Heterosporiiim is small, and consists of a group of species 

 separated off from Helminthosporium, from which it differs in the punc- 

 tate wall of the spores, &c. The name Heterosporium first occurs in 

 Klotzsch, Herbarium Vivmn Mycologicum, 1832. In this published 

 set No. 67 has a written label " Heterosporium maculatum Kl. MSS. 

 (novum genus Hyphomycetum) . In caulibus putrescentibus," and No. 

 69, similarly Heterosporium Ornithogali Kl. MSS. (novum &c.). In 

 foliis Ornithogali umbellati.'' There is no description either generic or 

 specific. M. C. Cooke, in a paper on black moulds read before the 

 Quekett Club,t called attention to these specimens of " Klotsch," 

 and pointed out that though the fungus called Heterosporium macula- 

 tum was probably a species of Cladosporium, that labelled Hetero- 

 sporium Ornithogali was the type of a distinct genus. This idea he 

 elaborates in an article in " Grevillea " v. (1877), p. 122. Here he 

 diagnoses the genus and includes therein certain species previously 

 placed in the genus Helminthosporium. One of these species was 

 Helminthosporium echinulatum B. et Br., which was recorded by them 

 as attacking Carnations {Gard. Chron. 1870, p. 352). Berkeley and 

 Broome afterwards described the same fungus as attacking Sweet 

 Williams, % but renamed it Helminthosporium exasperatum. Afterwards 

 Saccardo and Roumeguere § again renamed it Heterosporium Dianthi. 

 Saccardo later found the Heterosporium sp. which causes the Iris 

 disease and gave it the name Heterosporium echinulatum (B. et Br.) 

 Cooke, with a revised description, || and pubhshed a figure of it with this 

 name in " Fungi Italici," tab. 804. This is apparently the first refer- 

 ence to this fungus in Uterature, though de Thumen has three specimens 



* The name Helmisporium gramineum appears to be a manuscript name, and 

 if so the specific name cannot be taken up, but it does not affect the case under 

 consideration. 



I Journ. Quek. Micros. Club, v. (1877), p. 246. 



X Ann. Nat. Hist. 1873, " Notices of Brit. Fungi," No. 1380. 

 § Rev. Myc. iii. (1881), p. 57. 



II Michelia, ii. (1881), p. 364. 



