ON CARYOPHYLLACE/K 109 



a flat hyaline papilla, densely and minutely punctate, chestnut- 

 brown, 20 — 31 x 18 — 24 //,; epispore 2 — :]p, thick, not thickened 

 at the summit ; pedicels short, hyaline, deciduous. 



On Dianthus barbatus, D. Caryophyllus, D. chinensis. ( )n 



cultivated carnations practically all the year round. (Fig. 61.) 



The "Carnation Rust" was introduced into England on imported 

 plants about the year 1890 ; it sometimes occurs as an epidemic, causing 

 much injury. The teleutospore-containing sori are often clustered on the 

 leaves and stems in circinate or elongated swollen patches ; uredospores 

 are mixed with them. The punctation of the teleutospores is perceptible 

 only when they are viewed dry, and at the best is very indistinct. 



It is stated by Tranzschel and Fischer that this species is hetercecious, 

 and has its secidium on Euphorbia Gerardiana, but as this Euphorbia 

 does not occur in Britain, the parasite probably maintains itself here 

 without hcteroecism. It is remarked by Sydow that the same is true in 

 Switzerland, at least in certain cases; but see Fischer (p. 530) who 

 produced the fungus, from an lecidium on E. Gerardiana, on Saponaria 

 ocymoides, but not on Dianthus. The fungus has now spread round the 

 world in greenhouses, but only in the sporophytic stage ; the aecidium has 

 not been recognised anywhere except in Europe. The best means of 

 prevention are (1) the selection of resistant varieties, (2) good and careful 

 cultivation, especially sufficient ventilation. If spraying is resorted to, 

 potassium sulphide solution (h oz. to 1 gallon) is perhaps the best, but 

 dilute Bordeaux mixture or copper sulphate solution (1 lb. to 50 gallons), 

 or sponging with a rose-red solution of permanganate of potash have also 

 heen tried. The latter can be used even when the plants are in active 

 growth. Besides spraying, every infected leaf should be plucked off and 

 burnt as soon as discovered. This disease must not be confounded with 

 the outwardly similar "Fairy Ring of Carnations," caused by Heterosporium, 

 but the same remedies apply to both. 



Distribution : Europe, Western Asia, Japan, South Africa, 



North America, Australia. 



22. Uromyces Behenis Unger. 



JEcidium Behenis DC. Encycl. viii. 239. Cooke, Handb. p. 541 ; 

 Micr. Fung. p. 197. 



Uromyces Behenis Unger, Einfluss d. Bod. p. 216. Cooke, Micr. Fung, 

 p. 213. Plowr. Ured. p. 138. Sacc. Syll. vii. 559. Sydow, 

 Monogr. ii. 218. Fischer, Ured. Schweiz, p. 64, f. 48. 



sEcidiospores. yficidia usually hypophyllous, seated on 

 spots that vary both in size and colour (yellow or purple) 

 and are generally very conspicuous, solitary or collected into 



