120 



SEVENTEENTH REPORT. 



Measurements in Microns. 



CLASSIFICATION OF THE ORGANISM. 



The naming of the organism has presented some difficulty. The 

 shape and general character of the pjcnidium correspond to the 

 genus Phoma in its widest sense. But this genus of numerous and 

 widely variant species has been subjected to more or less sub- 

 division. Indeed Saccardo states that he himself would have radi- 

 cally subdivided the group if he had had more complete descriptions 

 of the species to guide him. 



The color of the spores has been considered carefully since this 

 'cliaracter is of such taxonomic importance. Saccardo in his first 

 'Compilation of the species of the ^phaeropsklaJcs transferred to 

 Coniothyrmm all species formerly referred to Phoma, in which the 

 spores were colored. But the extremely dilute color of the spores 

 :of this species is strikingly different from the spore color of the 

 ordinary Coniothyrmm. Furthermore, the examination of well- 

 authenticated species of the genus Phoma in the herbarium showed 

 that in many species there occurred a similar tinge of color. 



The convolutions of the hymenium an<l the occasional curved 

 spores gave a suggestion of ihe genus Ci/tospoiri, but in Ci/tofipoyn 

 the locules are distincl. The multiplicity of characters of this 

 fungus wliich enables it to partake of the ^'key'' characters of 

 several of the broad form-genera makes a decision somewhat diffi- 

 tnlt. One might bring considerable reproach against the system. 

 if it were not s(> well kno^^^l that ihe whole aiiangement is tem- 

 ]>ora ry and highly artificial. 



Saccardo had made a segregation from the old genus Phoma on 

 the basis of llic relation of the ])ycnidiiim to the substratum. This 

 genus which he called Apo.^phacria lias the characters of Phoma. 

 <'xcept that the jiycnidia are submerged or partly so. In this genus, 

 which the fungtis in (piestion also conforms with, there is a species 

 ♦loscribed by Saccardo. originally uiKlei- ihe name Phoma, which 

 fits tlie fungus with which 1 worked remarkablv well. After strict 



