222 BOTANICAL GAZETTE [MARCH 
the third spore-stage, usually designated by the Roman numeral III, and 
called teleutosorus, I propose felium (rédiov); derivatives telial, telio- 
Spore, etc. 
These four words and their derivatives have sufficient resemblance to 
corresponding terms now in use to suggest their meaning, and thus facil- 
itate their introduction; and yet they are all new words and are now brought 
before the scientific public for the first time. All the words are shorter 
than the corresponding ones now in use, except urediniospore, which is 
longer by three letters than uredospore, but no more difficult to pronounce, 
and for this the word at present in use, uredospore, may well be retained. 
No permissible shortening of the stem of this term has seemed feasible, 
and yet have the uniformity and classicism of the series preserved. 
I may be permitted to illustrate the use of these words by a similar 
sentence to that employed at the beginning of my paper. In the case of 
wheat rust, aecia appear on the leaves of the barberry in spring, preceded 
by pycnia; the aeciospores give rise in due course of time to uredinia on 
the wheat plant, followed by telia. A similar statement could be made 
for a Coleosporium, Phragmidium, or any other rust. One might explain 
the difference between the telial stage and the uredinial, or discuss the 
status of pycniospores as compared with teliospores or other sorts, oF he 
might point out that the sorus of a uredinium has the same essential 
structure whether without peridium and stylosporic, as in Puccinia; with 
peridium and stylosporic, as in Pucciniastrum, or without peridium and 
the spores in chains, as in Coleosporium; and so on. 
Finally, the acceptance of these terms would require that the following 
terminology for the receptacles, spores, etc., of the rusts should be sub- 
stituted for the series recently given by Saccarpo in his NV omenclatura 
mycologica, viz., sorus, pycnium, aecium, uredinium, telium, peridium / 
stroma. Mesospore, amphispore, stylospore, etc., are special descriptive 
terms, which may be extended indefinitely as need arises, but do not form 
part of the general category. Caeomospore, epiteospore, aecidiospores 
and other terms compounded from generic names should be wholly dis- 
continued. Peridium is to be preferred to pseudoperidium, in accord 
with the usage of DECANDOLLE, LEVEILLE, and many recent mycologists- 
Brevity, directness, and accuracy are excellent qualities to keep in mind 
- when deciding upon terminology.—J. C. ARTHUR. 
UE UNIVERSITY, 
Lafayette, Ind. 
