152 PUCCINIA 
Uredospores. Sori hypophyllous, on pallid irregular spots, 
scattered, minute, punctiform, pul- 
verulent, pallid-brown; spores more- 
or less globose, echinulate, yellow- 
ED brown, 16—24 y, with three (rarely 
ww four) germ-pores. 
Teleutospores. Sori similar, 
surrounded by the cleft epidermis, 
blackish-brown; spores ellipsoid, 
rounded and not thickened above, 
not constricted, rounded below, very delicately verruculose, 
brown, 26—86 x 16—24 uw; pedicels hyaline, very short. 
Fig. 104. P. Chondrillae. Te- 
leutospore and uredospores. 
On Lactuca (Prenanthes) muralis only. Not common. 
April—September. All three spore-forms may be found on the 
same leaf. (Fig. 104.) 
The ecidium of this species is not provided with a proper peridium 
and opens with a pore, never assuming the form of a cup; moreover the 
zecidiospores are more round than angular. The germ-pores of the uredo- 
spores are covered with a broad convex colourless cap, which swells up 
somewhat in water. The genetic connection of the three spore-forms has 
been proved experimentally by Jacky (Centralbl. f. Bakt. ix. 1902, p. 842), 
as also the fact that the parasite is not transmissible to other species of 
Lactuca. There is another ecidium also found on Lactuca muralis on the 
continent which possesses a well-developed peridium ; this belongs to 
Puccinia Opizit Bubdék, and has its teleutospores on Corer muricata. 
DISTRIBUTION: Europe generally. 
27. Puccinia variabilis Grev. 
Meidium Grevillei Grove, Journ. Bot. 1886, p. 129. 
Puccinia variabilis Grev. Scot. Crypt. Fl. pl. 75. Cooke, Handb. 
p. 500; Micr. Fung. p. 207, pl. 4, f. 82—3. Plowr. Ured. p. 150. 
Sydow, Monogr. i. 163. Fischer, Ured. Schweiz, p. 202, f. 158. 
Acidiospores. AXcidia amphigenous, on minute indetermi- 
nate yellow or purplish spots, solitary or a few loosely aggre- 
gated, cup-shaped, with whitish torn margin; spores subglobose 
or ovate, with orange contents, verruculose, 20—25 x 15—20 p 
Uredospores. Sori amphigenous, on very minute yellow or 
