208 FUNGI. 
known as Spheria (Pleospora) herbarum. First of all the very 
common mould called Cladosporium herbarum is constituted as 
conidia, and of this again Macrosporium sarcinula, Berk., is con- 
sidered tv be another condition. In the next place, Cytispora 
orbicularis, Berk., and Phoma herbarum, West, are regarded as 
pycnidia, enclosing stylospores. Then Alternaria tenuis, Pr.,* 
which is said to be parasitic on Cladosporium herbarum, is held 
to be only a form of that species, so that here we have (including 
the perithecia) no less than six forms or phases for the same 
fungus. As MMacrosporium Cheiranthi, Pr., often is found in 
company with Cladosporium herbarum, that is also open to 
suspicion. 
We have adduced in the foregoing pages a few instances 
which will serve to illustrate the polymorphism of fungi. 
Some of these it will be observed are accepted as beyond doubt, 
occurring as they do in intimate relationship with each other. 
Others are considered as scarcely so well established, but 
probable, although developed sometimes on different species of 
plants. Finally, some are regarded as hitherto not satisfactorily 
proved, or, it may be, only suspicious. In this latter group, 
however much probability may be in their favour, it can hardly 
be deemed philosophical to accept them on such slender evidence 
as in some cases alone is afforded. It would not have been 
difficult to have extended the latter group considerably by the 
addition of instances enumerated by various mycologists in 
their works without any explanation of the data upon which 
their conclusions have been founded. In fact, altogether this 
chapter mast be accepted as illustrative and suggestive, but by 
no means as exhaustive. 
® Corda, ‘‘ Prachtflora,”’ plate vii, 
