Uredu.] FUNGI. 385 



60. U. Potent, Spreiig. (Burnet Uredo) ; spots obliterated 

 rufous on the opposite side, sori subrotund scattered minute 

 hypogenous, epidermis bursting, sporidia subglobose orange, 

 accompanied by others which are pale cylindrical and slightly 

 curved. Spreng. Syst. 4. p. 576. Dub. Sf/n. p.S96. — Cceoma 

 Poterii, Lk. Sp. 2. p. 38. 



On Poterium Sanfjuisorba. Isle of Wight, Rev. M. J. Berkeley. — 

 The subglobose sporidia are often pedicellate. 



61. U. Euphorbice, Reb. (^Spurge Uredo); spots obliter- 

 ated, sori subrotund small scattered generally hypogenous sur- 

 rounded by the ruptured epidermis, sporidia pyriform abortive, 

 or subglobose and pedicellate, others perfect subglobose orange. 

 Peb. Neom. p. 354. Purt. 3. p. 297.— f/'. Helioscopice, Dec. 

 Fl Ft. 2. p. 232. Grev. Fl. Ed. p. 440.— Ccso77ia Euphorbi- 

 arum, Lk. Sp. 2. p. 39. 



On various species of Spwr/e, extremely common, especially on 

 E. Helioscojna and Peplus. — Some of the sporidia have rather long 

 peduncles. 



62. U. cylindrica, Strauss. (^Poplar Uredo) ; spots yellow, 

 sori subrotund here and there confluent, epidermis at length 

 bursting by a pore, some of the sporidia barren subglobose 

 pedicellate, others cylindric obtuse at either end orange. — U. 

 populina, Pers. ! Sgn. p. 219. Grev.l Fl. Ed. p. 442. — U. 

 Populi, Purt. 3. n. 1542. t. 27. Johnst. Fl. Bene. 2. p. 200. 

 — U. ovata, a. ^ /3. Grev. I. c. Johnst. Fl. Beriv. 2. p. 198. — 

 CcBOtna cglindricum, Lk. Lp. 2. p. 39. 



On Populus ni(ira, balsamifera, and trernula, also on Betula alba. — I 

 see very little diflf'erence between U. ci/Uadrica and U. ovata ; the 

 sporidia in the latter plant are seldom truly ovate, but more frequently 

 exactly as in U. cylindrica. Link appears to me correct in uniting 

 them. 



62. U. Saliceti, Schlecht. ( Willow Uredo) ; spots yellowisli, 

 sori subrotund solitary or disposed in circles with tlie centre 

 free, surrounded by the ruptured epidermis mostly hypogenous, 

 sporidia barren subglobose and pedicellate or pyriform, perfiect 

 subglobose orange. — (f. VitclUmc, Dec. Fl. Fr. 2. p. 231. 

 Grev. ! Fl. TJd, p. 437. Joknst. Fl. Berw. 2. p. 200. Desm. ! 

 531. — U. salicisy Grev.! I. c. — Cccuma Saliceti, Lk. Sp. 2. p. 

 41. 



On various Willows. Common. — Hoth the plants of Dr. (ireville, 

 referred to above, have the pyriform |)cdicellate sporidia, and appear to 

 be the same, exce()t indeed his F. Suliiis be U.Epitid, Kunzc, which 

 is distinguibheil princi[)ally by the paler sporidia and hardly ever con- 

 fluent sori. This can scarcely be determined without recent specimens. 



63.' U. Capredrum, Dec. (Sallow I'rcdo) ; spots obliterated 

 yellow on the opposite side, sori various in form nearly plain 

 here and there confluent hypogenous surrounded by the rnp- 



2 c 



