MYCOLOGICAL NOTES 207 



which the spores are smaller (2|-3 x 1-1| /u). A great deal of the 

 confusion which exists in the synonymy of the Coelomycetes is due 

 to the failm*e to recognize the fact (easily demonstrated on hundreds 

 of species) that the spores may gradually increase in size, as well as 

 alter in colour and complexity, as the fungus advances in age. Thus 

 all Di-plodia-sipores pass through the states of being (1) hyaline and 

 continuous, (2) pale-brown and continuous, and (3) darker brown and 

 septate, sometimes also increasing in size j^ar I passu SiS they change 

 in form and colour. In the first state they have been called Macro- 

 phomtty in the second SphcBvopsis, and in the third Diplodia, the 

 choice of genus being merely the accident of the occasion, the 

 matm'ity of the fungus, or the amount of time bestowed by the 

 observer on its investigation. Thus the actual specimens of Dr. Ellis 

 which are recorded in British Journals as MacropJioma Fraxini yield, 

 when more deeply probed, both Spliceropsis and Diplodia spores m 

 the same pycnidia ; and similarly I have proved by the examination 

 of a long and fine series of examples that Phoma Pinastri Lev. and 

 SpJicBvopsis Ellisii Sacc. are merely growth-states of Diplodia 

 Pinastri Grove. 



The same remark applies, with the necessary limitations, to the 

 three spore-sizes of the Pliyllosticta mentioned above, and one may 

 be forgiven for suggesting that there is no reason why Pliyllosticta 

 Crattegi Sa,CQ.= Cheilaria Gratcegi Cooke (in Grevill. xii. 25) should 

 not be considered to be the same species just before passing into the 

 Phleospbra-?,\j3L^e, when the upper part of the pycnidium is bursting 

 into lacinise. The Phleospora-stage would then be a later one, when 

 the elongated spores are being produced, but this is mere surmise. 



There is little, if any, diiference between the way in which these 

 two kinds of spores appear successively on the same mycelial bed, and 

 the way in which, in the Rusts, the same spore-bed will produce in 

 succession uredospores and teleutospores, and equally in both cases 

 each kind of spore may appear alone on its spore-bed, unaccompanied 

 by the other. The necessity then arises, when only a few specimens 

 are available, of describing each spore-form as if it were an indepen- 

 dent species, as was done on such a large scale in the Uredinales, but 

 also in both cases alike a wider knowledge, based on more numerous 

 examples, enables the evil to be remedied. 



If then, in studying this injurious disease of Hawthorn hedges *, 

 •we take the indications given above as proving that Phyllosticta 

 monogyna is the fore-runner of Phleospora Oxyacanthce, we should 

 expect to find a similar state of things in connection with other 

 Phleosporas, and that is exactly what we do find. For Phleospora 

 Aceris Sacc, is accompanied by Phyllosticta Platanoidis Sacc, 

 which at one of the intermediate stages looks like a Lepto- 

 thyrium, and has been called L. Platanoidis. In the same way 

 Phleospora JJlmi Wallr. is accompanied by a species of Phyllo- 

 sticta which apparently has not received a name, and a similar but 



* To help in the investigation of the fungi which grow upon the common 

 Hawthorn, the author will be grateful if mycologists will send to him, at the 

 University, Birmingham, any species of Cytospora which they may find upon that 

 host, with notes of the locality and mode of occurrence. 



