348 



MELAMPSORA 



Teleutospores. Sori hypophyllous, subepidermal, scattered 

 over the leaf singly ;ni<l in groups, pulvinate, \ — $ mm., 

 blackish-brown, nol shining; spores prismatic, rounded at both 



ends, :]') — 60x6 — 10 //.; epispore clear-brown, L— H/z thick, 

 scarcely thickened above, without evident germ-pore. 



Caeomata on Allium Cepa, A. ursinum and oilier species, 

 M.iy : uredo- and teleutospores on Populus nigra, P. balsami- 

 fera. < Fig. 260.) 



The description is chiefly after Klebahn. The teleutospores mature in 

 February of the following year; I find them shorter than given above, 

 viz. 25 32/*, and somewhat truncate at the summit. The cseoma of 

 Species of Melampsora on Allium is easily distinguished from the secidium 

 of Puccinia Winteriana on the same host by the absence of a peridium. 



(2) Melampsora Larici-populixa Kleb. 



('aeoma Lariri.< I'lowr. Ured. p. 2o'2 p.p. 



Mi-Li,,* psora populina Lev. ; Plowr. Ured. p. 242 p.p. (see note, 

 . "Biology," p. 243). 



M. Lariei-populina Kleb. in Zeitschr. f. Pflanzenkr. 1902, xii. 43. 

 Fischer, Ured. Schweiz, p. 502, f. 316. 



JScidiospores. Caeomata on hardly perceptible spots, scarcely 

 1 mm. long, bright yellowish-orange ; spores oval or roundish, 

 17—22x14 — 18 fi: epispore 14 — 2 p, thick, colourless, finely 

 verruculose. 



Fig. 261. M. Larici-populina. a, teleutospores ; b, uredospores and 

 paraphysis. On P. ontariensix, 



Uredospores. Sori mostly hypophyllous, in little groups, 

 causing yellowish angular spots on the upper side, rarely 



