SMUT. 



SMUT. 



dom to Smithfield market, but many more from 

 some districts than from others. The farmer 

 has personally little to do with the sale of his 

 cattle, but custom and interest induce him to 

 consign them to a salesman, who is acquainted 

 with all the butchers and dealers of the district, 

 and with the contractors. He sees at a glance 

 what is the state of the market ; he can tell 

 whether it is likely to rise or fall ; and com- 

 paring the lot which is intrusted to him with 

 othi-i s, and with the market generally, he knows 

 what they ought to fetch. The salesmen are 

 generally honourable men; they procure for 

 the owner the value of his cattle under all the 

 circumstances of the market, and although it 

 may mt always be so much as the grazier had 

 expected, it is more than he could have got 

 himself, and he is always sure of receiving his 

 : . See PocLTmr, SHEEP, SWINE, &c. 



SMUT. A disease affecting almost every 

 species of corn, the grains of which become 

 filled with a fetid black powder, instead of con- 

 taining farinaceous matter. Wet seasons, ani- 

 malcul.ne, organic weakness, deficiency of the 

 parts of generation, and other circumstances, 

 have been assigned as the primary causes of 

 this disease, but all the results of experience 

 are against the opinion that these are more 

 than (niingencies which aggravate the symp- 

 toms, ami accelerate the progress of the infec- 

 tion. That the smut does not arise from a de- 

 ficient fecundity is apparent, because it affects 

 roys the u'rain long before the sexual 

 organs are fully developed. Fogs, expo>ure 

 to intense sunshine when moist, or other atmo- 

 spheric influences upon the ear after it has 

 been protruded, have been assigned as causes; 

 but these cannot be productive of the mischief, 

 for the disease has been observed during an 

 early stage of the vegetation of the ear, and 

 long before it has escaped from the leafy en- 

 vHi'p.-s; this also dismisses the opinion enter- 

 tained In some that the disease occurs after 

 the grains are fully formed. It does not arise 

 from the too abundant moisture of the soil, be- 

 cause I have universally observed that the 

 driest parts of a field are as liable to bear an 

 infected grain as the most wet ; and we all 

 know that an infected plant stands surrounded 

 by others entirely untainted. Some persons 

 have thought that insects are the origin of the 

 disease; but the most accurate observations 

 have refuted this opinion, and shown that the 

 diseased grains may be an agreeable nidus for 

 the larvae, but that these always appear after 

 the disease is matured. Upon examining some 

 of the diseased grains, Mr. R. Somerville found 

 upon them a minute insect, in form like a 

 wood-louse, which I know from observation to 

 be a species of the acarus, and these he con- 

 sidered the cause of the disease. But this is a 

 conclusion unwarranted by observation, for 

 similar vermin are found upon the roots of the 

 Brassica tribe that are infected with anbury; 

 and, indeed, this genus of insects is invariably 

 found upon decaying vegetable matter; it is 

 their habitat. 



Other persons have thought that the grains 

 injured by the process of thrashing are most 

 liable to the disease; but this is refuted by the 

 fact that it appears in some years, and is 



scarcely to be detected in others. The Rev, 

 Dr. Hales bruised numerous grains of wheal 

 of different sizes with a hammer, but the result 

 convinced him that this opinion is erroneous. 

 Wolfins thought it arose from a monstrosity 

 of the embryo ; but M. Cymen has shown that 

 the male flowers of some plants suffer from 

 smut as well as the female, and the former we 

 know have no embryo. 



Some farmers have considered that pigeons' 

 dung induced the disease, but general expe- 

 rience is against this idea. Nor is the disease 

 the consequence of any defect of the sap, for 

 all the parts except the ear are healthy; and 

 there are some plants, observes M. Cymen, 

 having perennial roots, and which are vigor- 

 ous, yet their seeds ;ire annually attacked with 

 this disease. 



Having thus disposed of the several causes 

 which have been erroneously assigned, I will 

 now proceed to detail the more correct know- 

 ledge that has been accumulated respecting 

 this plague of our corn crops. 



This disease is severally termed smut, dust- 

 brand, blight, burnt corn, &c. In France it is 

 commonly known by the names ofcharbon and 

 nielle volante. Botanists, aided by the micro- 

 scope, have discovered that the cause of smut 

 is a parasitical fungus, which preys not only 

 upon the sap, but destroys the very organic 

 structure of the grain and chaff upon which it 

 fixes. The majority of naturalists agree in dis- 

 tinguishing the fungus by the title of Uredo 

 segetwn; but as it has oiher synonymes, these, 

 and the authors who have employed them, may 

 be usefully enumerated. Uredo segetum, Pursh, 

 n. 27; Chaos ustilago, Lin. Syst. Nat. 1326, n. 4; 

 Retii-nlinre des bits, Bulliard's Fungi, vol. i. p. 90, 

 plate 472, f. 2. Reticularia segetum, Withering, 

 iv. p. 388. Charbon, Tessier. Des Maladies des 

 Grains, 299. Bulliard describes this fungus as 

 globular, extremely fine, and attached to a fine 

 elastic thread. They are exceedingly nume- 

 rous, enveloping the seed and chaff of the 

 plants they affect, and are, as well as their own 

 still more minute seed, of an intense black 

 colour, having a disagreeable fetid smell, which 

 has been not inaptly compared to stale lobsters. 

 Mr. Kirby tells us that Mr. Lathbury examined 

 the dust of this fungus under a powerful mag- 

 nifier, and found it consisted of numerous mi- 

 nute particles, uniform in shape and size, much 

 smaller and blacker than those of the pepper 

 brand, and less easily separable: they seemed 

 to be contained in little irregular cells. This 

 dust or seed is the food of a small, shining, 

 black insect, the Dermestes ata of Marsham. 



Chemical analysis has demonstrated thai 

 this fungus effects an entire decomposition of 

 the vegetable particles of the grain it infects, 

 the saline constituents remaining nearly un 

 altered in the grain. Parmentier, Cornet, 

 Girot, Chantians, Fourcroy, and Vauquelin, 

 have successively examined it, and the result 

 of their researches is, that smutted grains of 

 wheat are composed, 1st, of about one-third 

 their own weight of a green, butyraceous, fetid 

 and acrid oil; 2d, nearly one-fourth of a vegeto- 

 animal substance, perfectly similar T o that 

 which comes from putrid gluten; 3d, a black 

 coal, one-fifth of their weight, similar to thai 

 4P 997 



