March 1907] Spore Forms of Spegazzinia Ornata Sacc 43 



SPORE FORMS OF SPEGAZZINIA ORNATA SAGC.^ 



ERNST A. BESSEY. 



The group, Tubercularieae Dematieae, to which genus Spe- 

 gassinia belongs is a rather artificial one containing some fungi 

 of undoubted close relationship but others whose affinities are 

 certainly with other groups. The genus Spegazzinia seems to 

 stand rather apart from) any other genera in this group on account 

 of the peculiar structure of the spores. The genus was first de- 

 scribed by Saccardo" from specimens collected in Italy, with the 

 single species 6". ornata. Some six or more species have since 

 been described so that representatives of this genus are known 

 to occur also in South America, Mexico and United States, and 

 doubtless many other parts of the world. The species are mostly 

 saprophytic,^ attacking different leaves, herbaceous stems and 

 wood, and in one instance observed by the writer, the dead skin 

 of a pomelo (Citrus deciunana) . They are most commonly found 

 on dead parts of grasses. The specimens examined by the writer 

 were collected by him in Florida on dead grasses, pineapple leaves 

 and pomelo skin, in addition to specimens collected by Lang- 

 lois in Louisiana (under the name of 6^. tessarthra) and a spec- 

 imen on unknown host from Texas. Through the kindness of 

 Professor Saccardo who sent the writer, on request, an authentic 

 specimen of 6". ornata collected by him in Treviso in 1877, i^ was 

 possible to identify all the above-mentioned specimens as be- 

 longing to this species. The differences between the specimens 

 on different hosts in different localities were not greater than the 

 difference between spores in the same lot of material. 



The mycelium within the substratum is colorless. On the 

 surface are produced here and there larger or smaller masses of 

 closely woven, thick-celled, dark-colored septate threads. In some 

 cases these bodies may attain a diameter of 5 mm. and be from 

 50-100 fjL thick, forming a definite sporodochium, but often there 

 are not more than one or two layers of threads. In such a case it 

 is difficult to see why the fungus is put in with the Tubercula- 

 rieae. Arising from these dark-colored threads are conidiophores 

 which bear two kinds of conidia (Fig. 3), long-stalked, spiny 

 conidia and short-stalked, smooth conidia ; the latter are borne 

 on stalks 5-8 /x long, occasionally longer, arising directly from the 

 hyphae of the sporodochium. These conidia are cruciately four- 

 celled and flattened in the plane in which the stalk lies (Figs. 6, 



^' Read before Section G., A. A. A. S., December, 1906. 



^ Saccardo, P. A. Spegazzinia, novum Hyphomycetum eenus. Pa- 

 dova. 1879. 



^ Spegazzinia trichophila Atkinson, a form lacking sporodochia, as 

 well as i". meliolicola Henn. and 5". meliolae Zimm. are found accom- 

 panying and perhaps parasitic upon species of Meliola. 



