71 



theory that they liave been introduced wlieii tlK^y produce sudden 

 and virulent epidemics, as in the case of the jjotato rot. The 

 presumption, I say, is in favor of this theory, but a presumption 

 it sliould be borne in mind is not a certainty. If Diaportlie para- 

 sitica is not a sj)ecies new to science, wluit is it, and wliere did 

 it come from? The microscopic structure of the chestnut tree 

 fungus as we now Ivuow it, is well known, and its habit and its 

 reproductive organs have been described and figured in nmny 

 publications accessible to everyone. What, however, is not so 

 generall}^ known is ^\\mt has been written in times past on fungi 

 found on chestnut trees in different countries, and a review of 

 what is known to mj^cologists in this connection may l)e instruc- 

 tive although, it must be admitted, the subject is not ver}'' easy 

 to follow. On account of dried specimens in the older herbaria 

 and a summary of the often obscure and conflcting descriptions 

 to be found in old treatises, even if desperately dull, will enable 

 us to form certain practical conclusions. 



When I first received fresh specimens of the fruiting fungus 

 of the chestnut tree I was struck by their great resemblance to 

 what is generally known in American herbaria as Eiidothia 

 gyrosa. Unfortunately most of the specimens of tliat species in 

 herbaria are sterile and from the habit alone one cannot be sure 

 of the species of a fungus of this group. The fresh fungus also 

 recalled a specimen I had seen in an Italian collection, and on 

 looking it up and comparing it miscroscopically with the fresh 

 material, I found the two to be identical. The gross structure 

 and the characters of the spores and asci were the same in both. 

 The Italian specimen to which I refer is No. 086, First Series of 

 the Erhario Crittogamico Italiana, issued in 18G3. The label 

 states that the fungus grew on chestnut trunks at Locarno on 

 Lake Maggiore, where it was collected by Daldini in 18G2. The 

 name there given is Endotliia radical is, but the question of the 

 name need not be considered at present. As other botanists 

 have examined the specimen just mentioned and agree as to 

 the identit}^ of the Endotliia radicalis and the Diaiwrtlie parasi- 

 tica, some having already expressed their opinion in print, we 

 may state definitely that our American chestnut tree fungus does 

 not appear to be new but to have been knoAvn on chestnuts in 

 Italy fifty yenrs ago. 



