UREDO. 



cluftered into little tufts, roundirti, and fomewhat turbinate, 

 with a tail, or elongation at the bafe, and interrupted by in- 

 ternal partitions. What are analogous to thefe in Uredo 

 are faid to be "uniform, generally globofe." This dittinc- 

 tion is clear enough, but the denomination of the parts in 

 queftion proves erroneous. This is evident from the elabo- 

 rate inveitigation of the blight in wheat, by the right hon. 

 fir Jofeph Banks, illuftrated by the microfcopic drawings 

 of Mr. Francis Bauer, republidied in Sims and Konig's 

 Ann. of Bot. V. 2. 51. t. 3, 4. By this treatife, and indeed 

 by Perfoon's own definition, it is manifeft, that his Sporula 

 are not feeds, but real feed-veffels, or capfuks. Therefore 

 the Uredo frumentt, Sowerby's Fung. t. 140. Lambert in 

 Tr. of Linn. Soc. v. 4. 193. Kirby ibid. v. 5. 122, which 

 was the fubjeft of fir Jofeph Banks's examination, and is 

 the Puccinia gramtms of Perfoon, Syn. Fung. 228, rather 

 anfwers to the charafter of the genus Llcea in the fame 

 work, p. 195, given as follows; " Head diftinft, round- 

 ifh or fomewhat indeterminate, brittle, without any fub- 

 jacent membrane. Seminal powder deftitute of threads." 

 We know not what is meant, in Perfoon's generic charafter 

 of Uredo, by the dillinftion between pulvis, powder, and 

 fporulu, feeds, nor whether the latter, if examined with equal 

 care, miglit prove, as in the Uredo frumentt, to be capfules. 

 The fubjeft indeed is in its infancy. Mr. Bauer has long 

 been collefting fafts and appearances to illuilrate it, which 

 are regiflered in his inimitable drawings, but materials are 

 not yet fufficiently plentiful to form therewith any fylte- 

 matic arrangement of thefe minute produftions, in which 

 the greatnefs of the Creator, and our own ignorance, have 

 long been acknowledged. Neverthelefs, we are obliged to 

 tliofe who have made any fcientific attempt at defining this 

 cryptogamic tribe, for prefent convenience, however imper- 

 fect fuch muft neceffarily be. In this light Perfoon (hines 

 confpicuoiis, and we fhall extraft what will beft illuftrate 

 his genus Uredo. The fubjeft is important in an agricul- 

 tural view, fome of thefe parafitical fungi being fuppofed, 

 at leaft, to be very detrimental to the corn, or other plants, 

 on which they grow. We are rather difpofed to believe 

 that the eft'eft has generally been miftaken for the caufe, and 

 that an injvn-y to the corn, from cold or wet, has merely dif- 

 pofed it to afford nounlhment for the fungi. This, how- 

 ever, is a theoretical queftion, not neceffarily connected with 

 the botanical part of the fubjeft. 



Perfoon defines 30 fpecies of Uredo, difpofed in four 

 feftions, according to the colour of the apparent powder ; 

 whether that powder be nzked feeds, or, as there is reafon to 

 fuppofe, from the above obfervacions, a congeries of excef- 

 fively minute capfules. 



Seft. I. Powder yello'wifh. Ri BIGO ; 16 fpecies. 



\5. mycnphila. Mufhroom Blight. Perf. n. I. (Mucor 

 chryfofpermus ; Bulliard Fung. v. i. 99. t. 504. f. i, and 

 t. 476. f. 4. With. v. 4. 402.) — Widely fpreading, ex- 

 tremely fine, yellow ; feeds folitary or aggregate, on capil- 

 lary ftalks, fimple or branched. — Found covering the whole 

 furface of fevcral kinds of Boletus, which grow in fhady 

 places, and even penetrating their fubllance, in the form of 

 an apparently impalpable yellow powder, flaining the fingers 

 when touched ; in Auguft and September, Dr. Withering 

 fays, it powerfully repels wet, like the feeds of a Lycopordium, 

 a fpecimcn in his pofTeffion not being moiftened, though im- 

 merfed in a fluid for a year. Perfoon remarks, that this 

 fpecies rarely occurs on any Agaric, and that the Boleti 

 attacked with it are not fully expanded before they languifh 

 and rot, being at firft involved in a white evanefcent downi- 

 nefs, and then copioufly impregnated with the above bright 

 yellow powder, which Bulliard compares to the pollen of a lily. 



U. jihhemilla. Ladies'-mantle Blight. Perf. n. 3. 

 Obf. Mycol. fafc. I. 98. — Crowded, yellow, breaking out 

 into nearly parallel lines. — On the leaves of Alchemilla vul- 

 garis, efpecially in mountainous fituations ; common in the 

 Hartz foreft. The leaves which bear this parafite are much 

 fmaller than ufual. The powder is nearly orange-coloured, 

 in ovate, elliptical, or more frequently linear fpots, like the 

 fructification of an Afplenium. Perfoon. 



U. Euphorbia heliofcopiic. Spurge Blight. Perf. n. 4. — 

 Scattered, nearly globular, prominent, yellow. — Frequent 

 in fummer on the plant mentioned, which when fo occupied 

 has always a pale fickly afpeft ; but whether in confequence 

 of the prefence of the fungus, or whether the latter attaches 

 itfelf to weak plants only, we know not. The fpots are 

 various in fize, deep yellow, prominent like warts. A 

 fmaller variety, more regular in fhape, is found on £. 

 exigua. 



U. linearis. Long linear Bhght. Perf. n. 7. (U. 

 longifTima ; Sowerb. Fung. t. 139.) — Linear, parallel, very 

 long, yellow, ilaining ; at length of a darker hue. — Ob- 

 ferved by Mr. Sowerby, on the leaves of Poa aquatica. 

 Perfoon fays, it is abundant in fummer on the ilraw and 

 leaves of barley, oats, and rye, but he fufpedls it may be 

 the early flage of his Puccinia graminis above mentioned. 

 If fo, the epithet " flaining" is not applicable. The fame 

 author indicates a fmaller and paler variety, found rarely 

 on the ftalks of Polypodium fragile of Linnxus. 



U. Rubi fruticofi. Bramble Blight. Perf. n. II Mi- 

 nute, nearly globular, powdery, bright yellow, deciduous. 

 — On the leaves of brambles, not uncommon. Perfoon 

 juftly obferves, that the powdery balls of this fpecies are fo 

 flightly attached to the leaf, that, when a branch is gathered, 

 they fly off, as it were elaflically, if perfectly ripe. 



\]. Rubi LUi. Rafpberry Blight. Perf. n. 12. Obf. 

 Mycol. fafc. 2. 24. — .Scattered, yellow, fomewhat conical, 

 breaking out in curved lines. — On the upper furface of 

 rafpberry leaves, towards the margin, where it forms curved 

 crowded lines, refembling the receptacles of an umbihcated 

 Lichen, Gyrophora, of a pale whitifh hue. In an advanced 

 ftate the powder is brownifli. 



U. Tufdaginis. Colt's-foot Blight. Perf. n. 13.— Scat- 

 tered in fomewhat concentric, reddifh-orange, dots ; at 



length confluent Common in autumn on the leaves of 



colt's-foot, which it finally covers with orange powder en- 

 tangled among the pubefcence. This often difappoints 

 thofe who are fearching for the equally common jiecidium 

 Tujfdaginis, {Lycoperdon epiphyllum of Linnaeus,) found on 

 the under fide of colt's-foot leaves, in the form of orange 

 dots, crowded together, each with its own white notched 

 I'oha. But thefe two fungi are very diftinft, though young 

 botaniils fometimes fuppofe one changes to the other. 



SeCt. 2. Powder-brown, bay, chefnut, or fomewhat blachijh. 

 NiGREDO ; 8 fpecies. 



U. Suaveolens. Sweet-fcented Blight. Perf. n. 19. 



Obf. Mycol. fate. 2. 24 Confluent, fragrant, unequal. 



Powder pale brownifh-purple. — Frequent in fummer on the 

 leaves of Gnicus arvenfis, [Serratula arvenjis Linn.) which, 

 according to Perfoon, is thus rendered barren. The leaves 

 attacked, at firft affume a thickened or fucculent appear- 

 ance, marked with little blackifh dots, or round tubercles, 

 and exhale a pleafant fcent. When the fungus arrivss at 

 maturity, a bright brown powder takes place of thefe tu- 

 bercles, and fpreads over the furface of the leaf. 



U. Ficia Fab/i. Bean Blight. Perf. n. 20. Difp. 

 Meth. Fung. 13. — Crowded, orbicular, or partly irregular, 

 depreffed. Powder brownifh-chefnut. — Plentiful on the 

 ftem, and efpecially on the leaves, of the common bean. 



U. huUata. 



