204 FUNGI. 



the peridia of Rcestelia appeared, and were developed. " This 

 trial of spores," says (Ersted, " bias conduced to the result ex- 

 pected, and proves that the teleutospores of Gytnnosporattgium, 

 when transported upon the sorb, give rise to a totally different 

 fungus, the Rcestelia cornuta, that is to say, that an alternate 

 generation comes between these fungi. They appertain in con- 

 sequence to a single species, and the Gymnosporangiwm ceased to 

 be an independent species, and must be considered as synony- 

 mous with the first generation . of Rcestelia. The spores have 

 been transported upon young shoots of the juniper- tree, and 

 have now commenced to produce some mycelium in the bark. 

 There is no doubt that in next spring it will result in Gymno- 

 sporangium." 



Subsequently the same learned professor instituted similar 

 experiments upon other hosts, with the spores of Podisorna, and 

 from thence he concluded that Rcestelia and Podisorna, in all 

 their known species, were but forms the one of the other. 

 Hitherto we are not aware that these resnlts have been con- 

 firmed, or that the sowing of the spores of Rcestelia on juniper 

 resulted in Podisorna. Such experiments should be received 

 always with care, and not too hastily accepted in their apparent 

 results as proven facts. Who shall say that Rcestelia would not 

 have appeared on Sorbus within two months without the sowing 

 of Podisorna spores? — because it is not by any means uncommon 

 for that fungus to appear upon that plant. It is true many 

 mycologists write and speak of Rcestelia and Podisorna (or 

 Gymnosporangiwm) as identical ; but, as we think, without the 

 evidence being so complete as to be beyond suspicion.. It is, 

 nevertheless, a curious fact that in Europe the number of species 

 of Rcestelia and Podisorna are equal, if one species be excluded, 

 which is certainly not a good Podisorna, for the reception of 

 which a new genus has been proposed.* 



Amongst the ascigerous fungi will be found a curious but inte- 

 resting genus formerly called Cordyceps, but for which Tulasne, 

 in consequence of the discovery of secondary forms of fruit, 



* This is Podisorna foliicola, B. and Br., or, as proposed in "Journ. Quetett 

 Club," ii. p. 267, Sarcos'roma BerJceleyi, C. 



