THE SMALLER. FUNGI. 633 
tercups, and similar plants. Although noticed abroad, as 
“a eg trom our author, the name does not occur in Dr. 
urtis list, nor the Tubercinia, whose bullate and blistered 
peridia attacks the European Trientalis, or star-flower, and 
may therefore reasonably be sought for by us in our north- 
ern New England co-species. The only approach to these 
complex smuts is in the Thecaphora, which differs from the 
maize smut, in its spores being made up of three or many 
regularly hexagonal parts, each echinate and beautiful 
microscopic objects, which I think I once received from my 
friend Charles J. Sprague, Esq., who is so e¢lebrated for his 
mycological knowledge of the fungi of Massachusetts. 
The usual idea we have of rust and rustiness is something 
similar to the rust of iron, and a rusty color is one of a yel- 
lowish brown hue. But the word is used in a wider sense 
Fig. 4. when employed to denote a par- 
ea ee asitic fungal, and we accordingly 
rare informed of “White Rust” 
in another of the smaller fungi, 
which, from its too intimate con- 
nection with agricultural crops, 
is worth some attention. Thus 
the white rust of the cabbage, 
turnip, ‘and similar plants, is 
owing to the presence of the 
Cystopus candidus (Fig. 43 4, 
fruit of shepherd’s-purse with 
white rust, C. candidus; b, por- 
tion of cabbage leaf with the 
same species; ¢, conidia of the 
same species. From Cooke), which appears in circular 
patches of white spots, and causes the leaves to become 
deformed, swollen and blistered, even before we can trace 
the cause of the mischief on the outside. These blistered 
pustules have a minute system of pranching threads, which 
traverse the pulpy parts of the leaves, and which threads, 
80 
AMER. NATURALIST, VOL. II. 

