ON CHENOPODIACEE 113 
25. Uromyces Bete Lév. 
Uredo Betae Pers. Syn. p. 220. 
Trichobasis Betae Cooke, Handb. p. 530; Micr. Fung. p. 225, 
Uromyces Betae Lévy. Ann. Sci. Nat. ser, 3, viii. 375. Cooke, Mier. 
Fung. p. 213. Plowr. Ured. p. 127. Sacc. Syll. vii. 536. Sydow, 
Monogr. ii. 224. Fischer, Ured: Schweiz, p. 10, f. 9. McAlpine, 
Rusts of Australia, p. 100, f. 148—9, 316, and pl. H. 
Nigredo Betae Arthur, N. Amer. FI. vii. 245. 
Spermogones. In little clusters, honey-coloured. 
ediospores. AKcidia amphigenous, often on rounded or 
irregular yellowish spots, collected into rather large clusters 
which are round or sometimes irregular and confluent, cup- 
shaped, yellowish, with a reflexed incised margin; spores 
delicately verruculose, pale-yellowish, 16—24 x 16—20 yu. 
Uredospores. Sori amphigenous, scattered, sometimes con- 
centrically arranged, thick, pulvinate, Jo 
circular, up to 2 mm. diam., covered by aa 
the epidermis which at length splits, 
then pulverulent, cinnamon; spores 
globose to obovate-oblong, sparsely and 
minutely echinulate, yellowish, 21—382 x Fig. 65. U. Betae. Te- 
16—26 1; epispore 243 thick, with amen tnt a 
two equatorial germ-pores. 
Teleutospores. Sori similar, but somewhat compact, dark- 
brown; spores globose to obovate, rounded and slightly thick- 
ened above, with a minute hyaline hemispherical papilla, 
smooth, pale-brown, 22—34 x 18—25 w; pedicels short, hyaline. 
On leaves of Beta maritima, B. vulgaris; also doing great 
harm to cultivated mangels. Acidia rather rare, April—June ; 
uredo- and teleutospores, rather common, May—October. 
(Fig. 65.) 
In May all four spore-forms can sometimes be seen on the same leaf. 
Kiihn says that the mycelium of the ecidia is perennial, and that its 
spores can reproduce the ecidia. If possible, the first leaves seen bearing 
the ecidia should be collected and burnt; this will check the disease at, 
the outset... If this is not possible, the plants may be sprayed with dilute 
Bordeaux mixture or with potassium sulphide solution. Since in mangels. 
the disease would chiefly be reproduced by teleutospores from old leaves 
G. U. 8 
