Melampsora.  24t 
Synonym. 
Melampsora tremula, Tul. Ann. Sc. Nat., 2nd series, p. 95. 
Cooke, “Hdbk.,” p. 522; “Micro. Fungi,” 4th edit. p. 219. 
Schrot., doc. cit, p. 362. 
Exxstccatt. 
Cooke, i. 85; it 154; “L. F,” 48. Vize, “Micro. Fungi 
Brit.,” 44. 
On Populus tremula, 
June to November. 
BIOLoGy.—Rostrup states that the scidiospores of this species 
are Caoma mercurialis and C. pinitorguum. The last-named species 
is not British. I have applied the germinating teleutospores from 
P. tremula to Mercurialis perennis in 1883 and 1884, but could 
obtain no result (Exp. 277-350). Although C. pindtorguum is not a 
British species, yet I applied the germinating teleutospores of this 
Melampsora to Pinus sylvestris (Exp. 351), but with no result. I 
have also tried the germinating teleutospores on Orchis maculata and 
latifolia, but with no result (Exp. 650-652, 654, 655). 
‘Hartig (“ Allgem. Forst-und Jagdztg.,” 1885, pp. 325-327) states that 
the eecidiospores of WZ. tremul@e are Ceoma laricis, and that by apply- 
ing the spores of C. Jaricés to the leaves of Populus tremula he 
produced the Melampsora, and adds that C. daricis and C. pinitorquum 
may either be two distinct species, or the same species modified by 
the difference of the host-plant. I have repeated Hartig’s experiments 
on three occasions (Exp. 710, 768, 769), by placing the germinating 
teleutospores of J. ¢vemul@ on young larch-trees, but without result. 
Professor Trail, however, finds these two species growing in company 
near Aberdeen. 
Probably more than one species of Melampsora occur on Populus 
tremula. 
Melampsora xcidioides. (D. C.) 
Uredospores—Sori small, roundish, surrounded by a white wreath 
of large crowded paraphyses. Spores spherical, elliptical, or 
ovate, 17-24 X 15-17. Spore-walls colourless, echinulate, 
contents orange-red. Paraphyses clavate, 40-60 X 15-20. 
Teleutospores—Forming small brown crusts. Spores cylindrical, 
brown, cohering laterally, apex truncate, 50 & Tom. 
R 
