240 



F A [i. M E R S ' R E G I S 1' E R. 



[No. 4 



smut only affects irrain when the growth is in an 

 advanced slate, thinks it is caused by a total 

 want ol" sap at the root. ( Observations on Ilas- 

 bandry.) W. Ellis, aixain, the well known eco- 

 nomical farmer ol" Little Gaddcsden in Essex, is 

 led to conclude thai smut arises chiefly from want 

 of nourishment in the root. 



Debility in growtli, besides, is quite inconsist- 

 ent with one of the conmiunest appearances of 

 inltjcted corn, that of standin<!; considerably hiuher 

 in the field ihan the level of the tops of the heal- 

 thy plants, a fact remarked by almost every writer 

 on the subject. 



It will not be requisite to spend more time in re- 

 futinjT the mistaken opinions which have been pro- 

 mulirated; but we cannot pass over one which rc- 

 liirs chiefly to rusl. 



5. Influence of the Barberry Bush. — In conse- 

 quence of the leaves of the common barberry ex- 

 hibiting a similar atiection to the rust in corn, far- 

 mers, both in England and on the Continent, have 

 concluded that the infection spreads from the bush 

 in the hedge to the corn in the field; and this notion 

 is sometimes strentrthened from the rust appearing 

 in patches and stripes among the corn, as if it had 

 been carried thither by the wind from the barberry 

 bushes. 



Sir Joseph Banks, in mentioning this oninion, 

 says, that "the village of Rollesby in Norfolk, 

 where barberries abound and wheat seldom suc- 

 ceeds, is called by the opprobrious appellation of 

 Milldew Rollesby." Biit thoujjh he himself speaks 

 with doubt upon the subject, he does not absolutely 

 discountenance the idea. (On Blight in Corn, pp. 

 10, 11.) M. Decandolle, in referring to this pas- 

 sage, says, he "would not have agitated the ques- 

 tion, had it involved a plant less important than 

 wheat, or a philosopher less distinguished than Sir 

 Joseph Banks;" tor it is most obvious to tlie slisjht- 

 est observation, that corn is often not at all infected 

 even when the barberries in the vicinity are cover- 

 ed with their peculiar rust; and again, corn is fi-e- 

 quently covered with rust when the adjacent bar- 

 berries are quite free from it. (Eacyd. Method. 

 Bot. vi. 210. A periodical writer remarks, that 

 the rust in the ash, the elm, the barberry, the rose, 

 the bramble, the coltstbot, the nettle, the groundsel, 

 the dandelion, and numerous other plants, "is as 

 different in species as the plants themselves, and 

 therefore it would be no less rational to maintain 

 that a field of wheat would spring up if we should 

 sow barberries, than that the rust irrowinfjon these 

 should produce the corn-rust. Should it be said, 

 that it is the difference of the nutriment of the 

 fungus which causes the ditli^rence, I would ask, 

 whether a difference of soil would produce rye or 

 oats where wheat seed only had been sown." 

 (Paxton's H.)rt. Reg. ii. 467.) 



j^scertained cause of Smut, Canker, and Rust. — 

 From the resemblance of smut to the powder con- 

 tained in the well known liingus termed the putf- 

 ball ( Lycoperdon, ) it was conjectured by some of 

 the early writers that it was identical therewith, 

 not adverting to the great distinction of the two 

 places of growth. Even the distinguished bota- 

 nist Jussieu is reported to have said that the smut 

 was caused by the globe puff-ball; and Sir H. Davy 

 was led to adopt a similar notion from the resem- 

 blance of the smut and the puff-ball when chemi- 

 cally analysed. — y/gricul. Chemistry. 



Tiie Abbate Fontana, in 1767, however, was 

 certainly the first writer who had any clear no- 

 tions on the subject, and his magnified figures in 

 his excellent little work are as well calculated to 

 prove his accuracy and to uproot popular preju- 

 dice, as tlie researches of his disfinguislied coun- 

 tryman Redi were to destroy the iimcies about ihe 

 spontaneous generation of insects by puiridiiy, 

 blighting weather, and similar vague and imj os- 

 sible causes. 



But thou<rh this idea was so well developed by 

 Fontana, and has sinc,e been elucidated by Bauer 

 and others, tfie mode in which funguses grow and 

 are propaijaled was very imperiectly understood, 

 and one leading error oti the subject is still very 

 miiversally maintained, namely, thai the growth 

 of the I'unguses in question, as well as the attacks 

 of msects on growing plants, must he taken only 

 as a consequence of previous disease in the plants 

 attacked. The truth is, that in the case of smut, 

 canker, and rust, as well as in the case of all plant- 

 lice and catterpillars, such as the hop-fly and wire- 

 worm, it is uniformly the healthiest plants which are 

 attacked. It is singular that such a mistake should 

 in this instance have become popular, when in other 

 cases, such as the attacks upon fruit made by wasps 

 and birds, it is universally believed the best and 

 finest are selected, though even this is not quite 

 correct, (or a wasp or a sparrow will more readily 

 nibble at a wounded grape or a damaged jargo- 

 nelle pear than at the best sound fruit on a tree. 



DutrucheVs Discovery of the mode of growth in 

 Funguses. — In a damp cellar where wine was 

 kept, M. Dutrochet, one of the most original ob- 

 servers of the day, remarked, about two or three 

 years ago, a while looking net-work ot" fibres, 

 which previous botanists (Bulliard, Champignons 

 Era'}/;.) had described as a species of crow-silk 

 (Byssus). Being struck with its peculiar manner 

 of growth, he watched it with careful attention, 

 and got x\I. Turpin, probably the best botanical 

 draughtsman in Europe, to take drawings of it in 

 ever}' stage ot its growth. It would lead us too 

 far Irom the object of this paper, to detail all his 

 interesting observations. The general result was, 

 that the supposed crow-silk was not, as had been 

 supposed, of the genus Byssus at all, but the gen- 

 uine stems, hitherto known as such, of a mushroom 

 {Agaricus crispus, Turpin); the mushroom itself 

 being the Ouit only, and not as hitherto believed 

 the whole plant. According to this view, then, it 

 would be as correct to consider a bunch of grapes 

 with their truit-stalk a complete plant, as (he fruits 

 termed mushrooms, puff-balls, or puddock-stools; 

 all these being only the fruits of plants generally 

 growing under ground, in the Ibrm of small white 

 or grey fibres of net-work, and termed improperly 

 by gardeners spawn, indicating that it is the seed 

 of mushrooms, whereas it is ihe genuine plants. 



M. INI. Dutrochet and Turpin further discovered, 

 that the seeds, or, as they are termed by bo'anist.?, 

 sporules, consisting of" minute globular bodies, are 

 contained in the cells of funcpus fruit in prodigious 

 numbers, and they succeeded in observing these 

 germinate and produce young plants like their pa- 

 rent. There cannot, therefore, remain a doubt, that 

 funguses are produced iiom seeds in the same way 

 as all other vegetables, though these seeds or spo- 

 rules are exceedingly smaller than those of green 

 plants — being as subtle, JVl. Fries remarks, some- 

 times as smoke. — Syst. Mycol. Intr. 





