152 
CHARLES B. PLOWRIGHT. 
mere waste of time to have proved what is already known to 
be true. The other twenty cultures were made upon other 
host plants, and were mostly repetitions made over and over 
again before I felt myself justified in differing from him. 
Experiments 1 to 100 were made in 1882. 
„ 101 „ 244 „ „ 1883. 
„ 245 „ 426 „ „ 1884. 
The Ranunculi iEcidia. 
History of the Subject. — The various members of the 
Ranunculus family are peculiarly liable, as Schroter 1 has 
pointed out, to be affected with the secidiospores of various 
Uredines. In fact in this country no less than eleven species 
have iEcidia occurring more or less frequently upon them, 
whereas only four species have either teleutospores or uredo- 
spores affecting them. The secidial host plants belonging to 
the Ranunculacese in this country are Clematis vitalba, L. ; 
Thalictrum alpinum, L. ; flavum, L. ; Anemone 
nemorosa, L.; ranunculoides, L. ; Ranunculus acris, 
L. ; repens, L. ; bulbosus, L. ; ficaria, L. ; Caltha 
palustris, L., and Aquilegia vulgaris, L. ; while teleu- 
tospores and uredospores only occur on Thalictrum flavum, 
L. ; Anemone nemorosa, L. ; Ranunculus ficaria, L. ; 
and Caltha palustris, L. 
The author above quoted has shown that many of these 
iEcidia are heteroecismal. He pointed out that those writers 
who, like Fuckel 2 and Cooke , 3 have affiliated the very common 
HScidium upon R. ficaria with the Uromyces, which also occurs 
upon this plant, were wrong in so doing; that these two fungi 
are distinct species, having separate and altogether unlike life- 
histories, and that their occurrence upon the same host plant is 
a mere accidental circumstance. He further showed that the 
iEcidium in question is really connected with a Uromyces which 
1 Schroter, * Cohn’s Beitrage zur Biologie der Pflanzen,’ vol. iii, Heft 1, 
p. 59. 
2 Fuckel, ‘ Symbol. Mycol.,’ p. 64. 
s Cooke, ‘Uromyces in Grevillea,’ vol. vii, p. 136. 
