228 



&V THE BLIGHT IN CORN. 



ever to be obferved that barley rifes from the flail lighter this 

 year than was expected from the appearance of the crop when 

 gathered in. 

 tittle informs- Though diligent enquiry was made during the laft autumn, 

 "db inquiry"* no ' n ^ ormat ' on or * importance relative to the origin or the 

 refpeding ' progrefsf of the blight could be obtained: this is not to be 

 blight; but its won d ere( j a {. f or as n0 one f tne per f ons applied to had any 



caule being now ' r 



explained, the knowledge of the real caufe of the malady, none of them 



remedy it is 

 hoped will be 

 difcovered. 



Progrefs of the 

 infection* 



Increafe of the 

 fungus incalcu 

 iably rapid ; 



and its periods 

 of generation 



very quick. 



could direct their curiofity in a proper channel. Now that its 

 nature and caufe have been explained, we may reafonably 

 expe6t that a few years will produce an interefting colle£tion 

 of fads and obfervations, and we may hope that fome progrefs 

 will be made towards the very defirable attainment of either 

 a preventive or a cure. 



It feems probable that the leaf is fir ft infe&ed in the fpring, 

 or early in the fummer, before the corn (boots up into 

 ftraw, and that the fungus is then of an orange colour;* after 

 the ftraw has become yellow, the fungus alTumes a deep cho- 

 colate brown : each individual is fo fmall that every pore on 

 a ftraw will produce from 20 to to fungi, as may be feen in the 

 plates, and every one of thefe will no doubt produce at leaf! 

 100 feeds; if then one of thefe feeds tillows out into the num- 

 " ber of plants that appear at the bottom of a pore in Plate IX. 

 Fig. 1, 2. how incalculably large muft the increafe be ! A few 

 di leafed plants fcattered over a field muft very fpeedily infect 

 a whole neighbourhood, for the feeds of fungi are not much 

 heavier than air, as every one who has trod upon a ripe puff- 

 ball muft have obferved by feeing the duft, among which is its 

 feed, rife up and float on before him. 



How long it is before this fungus arrives at puberty, and 

 fcatters its feeds in the wind, can only be guelfed at by the 

 analogy of others ; probably the period of a generation is 

 fhort, poifibly not more than a week in a hot feafon : if fo, how 

 frequently in the latter end of the fummer muft the air be 

 loaded as it were with this animated duft, ready, whenever a 



* The Abbe Teflier, in his Traite des Maladies des Grains, tells 

 us that, in France, this difeafe fuft fhews itielf in minute Ipots of a 

 dirty white colour on the leaves and items, which fpots extend them- 

 selves by degrees, and in time change to yellow, and throw off a dry 

 orange coloured powder, pp.201, 340. Note of Sir J. B 



gentle 



