LASIODIPLODIA. 453 



its pycnidia are pilose, scattered or subconfluent, with long 

 internal paraphyses ; yet its describers do not consider that 

 it falls witliin their genus Lasiodiplodia. It has two of the 

 characters of that genus, but its pycnidia are not embedded 

 in a true stroma. After this example, we may be quite certain 

 that most of the forms of Botryodiplodia theobromce Pat. 

 would not be considered as Lasiodiplodia by the authors 

 of that genus. Nor would Lasiodiplodia Thomasiaiia 

 Sacc, whose pycnidia are " modo solitariis, mode paucis 

 coacervatis." 



Bancroft (24) falls into the same error as Brick. In 

 discussing Botryodiplodia theobromce, he states: "But these 

 authors all overlook the presence of paraphyses in the pycnidia, 

 on account of which the fungus must be regarded as 

 a Lasiodiplodia.'' Reference to the characters of the genus 

 will show that this is incorrect, and Diplodia paraphysata 

 proves that it was not the authors' idea of their genus. 

 The distinguishing character of Lasiodiplodia is the pilose 

 stroma. 



The above list of Diplodias which possess paraphyses is in 

 aU probability far from complete. Many of the older de- 

 scriptions include measurements of "basidia," and it appears 

 probable that in some cases these may have been paraphyses. 

 For example, the "basidia" of Patouillard's Botryodiplodia 

 theobromce must have been paraphyses. If the presence of 

 paraphyses is to be considered of subgeneric importance, we 

 are at once beset with difficulties. It would not be at variance 

 witli the information available at present, if we were to 

 suppose that very many, if not all, species of Diplodia are 

 furnished with paraphyses, but that these attain a length 

 greater than that of the basidium plus its spore only in 

 tropical species. It would be necessary to decide whether a 

 given filament were a paraphysis, or a basidium deprived of 

 its spore, and tliis would give occasion for endless differences 

 of opinion. The difficulty might be evaded by counting as 

 paraphyses only those filaments which exceeded the length 

 of a basidium plus its spore, but the distinction would be 

 purely artificial, corresponding to that between Diplodia and 

 Microdiplodia. 



6(11)10 (59) 



