ON COMPOSITE 147 
21. Puccinia Lapsane Fckl. 
Heidium Lapsanae Schultz, Prod. Flor. Starg. p. 454. Cooke, Journ. 
Bot. ii. 38, pl. 14, f. 2; Handb. p. 543; Micr, Fung. p. 198. 
Trichobasis Lapsanae Cooke, Micr. Fung. p. 224. 
Puceinia Lapsanae Fckl. Symb. Mye. p. 53. Cooke, Micr. Fung. 
p. 207. Plowr. Ured. p. 149. Sacc. Syll. vii. 607. Sydow, 
Monogr. i. 112. Fischer, Ured. Schweiz, p. 203, f. 159. 
Spermogones. Crowded in little clusters, epiphyllous, honey- 
coloured. 
4Aicidiospores. Aicidia amphigenous, somewhat crowded on 
large, roundish, purple spots, flattish, with torn white reflexed 
margin; spores subglobose or ovate, nearly smooth, orange, 
16—21 x 13—17 p. 
Uredospores. Sori amphigenous, very minute, round, very 
numerous, often confluent, pulverulent, chestnut- 
brown ; spores globose to ovate, delicately echinu- fo 
late, pale-brown, 17—22 x 15—18 p, with two 
germ-pores. 
Teleutospores. Sori amphigenous, minute, 
scattered, numerous, pulverulent, blackish-brown; fig 99, p, 
spores ellipsoid or ovate, rounded at both ends, Perc lea 
A ‘ eleutospore. 
not thickened above, scarcely constricted, very 
delicately punctate, chestnut-brown, 22—33 x 17—26 yu; pedi- 
cels hyaline, slender, short, often oblique. 
On leaves and stems of Lapsana communis. Very common. 
Aicidia, March—May ; uredospores, April—June; teleutospores, 
June—September. (Fig. 99.) 
The ecidium of this species shares with those on Ranunculus Ficaria 
and Potentilla Fragariastrum the distinction of being the earliest Uredine 
to make its appearance in the spring. It may be found on the young 
leaves of the seedlings almost as soon as they are formed. Plowright 
demonstrated (Expt. 499, May, 1885) that all three spore-forms belong to 
the same life-cycle. The mycelium of the ecidia, when occurring on the 
petioles, causes them to become pale and swollen ; on the leaves it often 
produces conspicuous purple spots which bear the spermogones on the 
upper surface. 
DistRisuTion: Europe, Syria, Japan. | 
10—2 
