PAPERS ON BOTANY 237 
mum spore length as P. graminis. The measurements for 
spore length of different specimens of P. gramims show as 
great a variation among themselves as the spore length of 
P. graminis shows when compared with the other five species. 
THE SPECIES OF THE GENUS PHYLLACHORA 
The determination of the species of this fungus has raised 
the question of the validity of various of the species now re- 
garded as distinct in the genus Phyllachora. For a satisfac- 
tary comparison of the species a tabulation was made from 
Saccardo’s “Sylloge Fungorum.” The arrangement of this 
tabulation is in the order of maximum spore length, and the 
table includes specific name, volume, and specific number of 
the “Sylloge Fungorum,” spore measurements, ascus measure- 
mients, the host family indicated by number taken from De 
Dalla Torro and Harms “Genera Siphonogamarum.” The 
species that are excluded in the revision by Sydow and Theis- 
sen are also indicated. 
Saccardo lists four hundred and sixty-nine species on eighty- 
three different host families. A large majority of these are 
from the tropics. An indication of the very large number 
given on single families is afforded by the fact that sixty-three 
species are found on the Gramineae, forty-five on the Legum- 
inosae, twenty-seven on the Moraceae, and twenty on the Com- 
positae. The three species P. bromi, P. maydis, and P. gram- 
imis occur on the same host family and are similar in all of the 
most significant specific characters, It is doubtful if there are 
sufficient differences here to give these three distinct specific 
rank, 
Oi the species listed by Saccardo one hundred and thirty- 
three were described from immature material without spores 
and of these nine species were on Gramineae, five on Moraceae, 
nine on Leguminosae, and nine on Compositae. Such descrip- 
tions are, of course worse than valueless. 
The presence or absence of paraphyses is regarded as of 
specific value. Sydow and Theissen even consider this of 
sufficient systematic importance to be a generic sign. The 
list by Saccardo, however, contains eighteen species said to be 
without paraphyses and in the description of two hundred and 
