202 CRYPTOGAMIA FUNGI. 



The infected leaves are often irregularly spotted with pale 

 yellow* 



29. U. umbellatarumj spots scattered, small, subcircular or oval, 

 yellowish-brown ; capsules ovate, pellucid, sometimes stalked. 

 Caoma umbellatarumj LINK in WILD. vi. ii. 23. Uredo Cynapii, 

 Bot. Gall. ii. 900. 



Hab. On the under surface of hemlock leaves, abundant. 



The Uredo Heraclei of GREVILLE is probably identical with 

 this species. 



30. U. Violarumj spots small, subcircular, brown, thickly 

 scattered on the leaf; capsules globular, shortly pedicled. DE- 

 CAND. Fl Franc, vi. 73. Bot. Gall. ii. 899. 



Hab. On the dog's violet, attacking both sides of the leaf. 



31. U. suaveolensj brown, the spots at first scattered, circular, 

 very numerous, becoming confluent and covering the whole leaf; 

 capsules globose. HOOK. Scot. ii. 15. GREV. Fl. Edin. 434. 

 Mridium Cardui, Sow. Fung. t. 398. f. 5. 



Hab. On the leaves of the creeping and marsh thistles, 

 common. 



This species attacks both surfaces of the leaf, but principally 

 the under, which it covers with crowded powdery spots, 

 small, distinct and yellowish at first, but becoming more 

 or less confluent in its progress, and of a dark brown co- 

 lour. It exhales a strong sweet honey-like smell, percep- 

 tible, however, only in the first stages of the plant. The 

 following remark of SOWERBY is consistent with my own 

 observation : " Two or three sorts of flies are occasionally 

 found dead on this plant (creeping thistle) at the time of 

 the JEcidium being upon it, which is after wet weather in 

 the summer, or early in autumn : being apparently tempted 

 by its flavour, they over-eat themselves, or else are de- 

 stroyed by some poison." 



32. U. oblongata, spots oblong, reddish brown, bursting through 

 the epidermis longitudinally; capsules subglobular GREV. Crypt. 

 Fl,t.l2;Fl. Edin. 437. 



Hab. On the leaves of the great wood-rush. 

 The spots are surrounded by a reddish-crimson halo. This 



