M. C. COOKE, NOTES ON PODISOMA. 259 



justification of the term " basiclia," as applied to the protospores 

 of Podisoma, Tulasne observes that "the pretended bilocular sporidia 

 of these fungi become organs analogous to the basidia of the 

 Tremella3 and Exidia3, which are divided into two or four cells,* 

 consequently the tubes or filaments which spring from these sporidia 

 must be a kind of spicules, or compound sterigmata, which their large 

 dimensions and special structure doubtless render very different 

 from the ordinary sterigmata of the Hymenomycetes, but which 

 are evidently allied to the singular spicules which are proper to the 

 Tremellas. Finally, the spores of Podisoma have completely the 

 form and organisation of the spores of Tremella mesenterica, and 

 are similarly attached to their immediate support," and again he 

 says, " the affinities which ought to be recognised between the 

 Podisoma and the Tremellce have not all their foundation in the 

 reproductive apparatus. The body itself, or the parenchyma, pre- 

 sents an organization which is tolerably analogous to that of the 

 Tremellini, since it is exclusively formed of long filaments and the 

 thick mucilage which holds them together ; only these filaments 

 are nearly solid, so thick is their constituent membrane, and they 

 are but rarely ramified. In Podisoma juniperi- communis (Fr.) they 

 undergo, at the period of the dissemination of the spores, a kind of 

 dissolution which confuses their substance with the surrounding 

 mucilage. Those of Podisoma fuscum (Corda) are preserved longer 

 entire and distinct, but finally experience the same fate." 



These views were subsequently modified considerably, after a 

 more complete acquaintance with the germination of the Uredines, 

 and in the communication to the French Academy already cited, 

 Tulasne expressed his full conviction that the true affinities of 

 Podisoma were with the Uredines. "j" 



Of late years the attention of mycologists has been directed very 

 much to a kind of alternation of generation which takes place 

 amongst the Uredinous Fungi. De Bary and Tulasne have each 

 contributed something to the history of these extraordinary phe- 

 nomena ; but the relations of the Tremelloid Uredines to other 

 fungi have only been studied by Dr. Oersted, of Copenhagen, who 

 maintains, as the result of his experiments, that all the species of 

 Podisoma are but conditions of the horned cluster cups (Bcestelia), 



* See Tulasne in "Annalesdes Sciences Nat.," 3rd Ser., vol. xix. (1853), 

 pp. 193, et. seq. 

 t Comptes Eendus, 20th June, 1853. 



