B Y S
B Y S
the neighbouring bodies e . — [ c Bra/8. Di&. -Bofc T. I. vec GoffipiuTn. Mem. Acad. Infer. T. 7. p. 339, feq. Gatmet, Dict.Bibl. T. l. p. 333. e Mem. Acad. Scienc. an. 1712. p. 270, feq.]
In reality, the antients feem to have applied the name indiffe- rently to any kind of matter that was fpun and Wove finer than wool: fo that it is probable there were divers forts of byffus. This is certain, that Ariftotle gives the name byjfus to the hair orfdken threads of the pinna marina; whether it were on ac- count of its refemblancc to the byjfus of which cloths were made, or whether it were that this was the true byjfus itfelf. What countenances this latter opinion is, that the byjfus of the pinna marina may be fpun, and confequently there is little doubt but that in ages when filk Was fcarce, it might be ufed in the cloaths of great men. Add, that this byjfus, though grofsly fpun, appears much finer and more beautiful than wool, and comes not much iliort of filk. Stockings and other like works are ftill made of it, which would be more valuable if filk waslefs common. To fpin this byffus, they leave it fome days in a cellar to moiften and grow foft, after this they comb it, to get out the impurities, and, Iaftly, fpin it as they do filk. Mem. Acad. Scienc. loc. cit. p. 271.
The pinnae marinSe being plac'd upright on the tips of their fhells, have occafion for fuch threads, which they fpread all a- .round them like fo many ropes from a malt, to keep themfelves iteady in this iituation. 'Tis probable thefe threads are fpun by the pinna after the fame manner as thofe of the fea mufcle, defer ibed by Mr. Reaumur, to which they bear a refemblance; only that they are finer and more filky; differing from them, according to Rondeletius, as filk does from hemp. Mem. A- cad. Scienc. ann. 1712. p. 272.
Authors ufually dift'mguifh two forts of byjfus, that of Elis, and that of Judea, which was the fined:. Of this latter were theprieftly ornaments made. Bonfreriusnor.es, that there muft have been two forts of byjfus, one finer than the ordinary, by reafen there are two Hebrew words ufed in Scripture to denote byjfus, one of which is always ufed in f peaking of the habit of flie prieffs, and the other of that of the Levitts. Tfev. Dii5t. Univ. T. 1. p. 1297, feq. Bvssus, in botany, a word ufed to exprefs a genus of moffes the . moft imperfect of the whole clafs of vegetables. The charac- ters of this genus are, that the mofles of it are compofed of fimple and uniform parts, and always appear in form of ex- crefcences, either of a woolly or of a dufty matter. It feems properly a genus of vegetables of a middle kind, between the mumrooms and the mofles, but moft approaching to the latter, in that the feveral fpecies of it are of a longer duration, and want that fleflry texture which di vHnguifh.es the fungus clafs, and in that they never produce heads, nor have any thing of the figure or texture of fungi. The byjfi differ from the con~ fgrva; in that they do not grow in the water, and in their be- ing compofed of flenderer and fhorter filaments. They have not yet been difcovcred to have either flower or feed, but appear always in form of threads or of a light down, or fine powder, on tiie furfaces of many different bodies, hut principally on fuch as are liable to putrefaction. Micheli, in his Nova genera p/an- tartiitt, p. .no. mentions the feeds of fome of the byffujis; but
later obfervcrs, and particularly the indefatigable Dillenius.were never able to obferve them. This laft author lias defcribed 20 fpecies of thefe fmall plants. 1. The green paper-like byjfus. This is found in fpring covering the furface of ffanding wa- ters, with a fine green fkin. 2. The whitc-waih byffus, a kind found incrufting over the furfaces of mofles, and other fub- ftanccs, in form of mortar or white- waftiing on a wall. 3. The mealy byjfus. This is found in great plenty on the trunks of old trees, on the decaying branches of other mofles, and on the ground, in form of a fine white or hoary powder. 4, The yellow powder byjfus. This crufts over old walls, trees, and the tiles of houfes, with fpots of a yellow downy matter. 5. The green clutter byjfus. This is compofed of a number of green globules cluttered together, which are very fma'1, and, when viewed with a microfcope, appear gelatinous and tranf- parent. It is found in fummer on the fides of hollow ways, where the fun does not come. 6. The downy violet-coloured byjfus. This has by fome been called a fmall fungus, creeping like a herpes on wood; it is ufually found on old boards^ fometimes on the rotted ftacks of mofs,and is of a Ianuginous ftrucr.ure, confifting of fine fhort threads : it flourifhes princi- pally in winter. 7. The pleafant green vcrdigreafe- coloured byffus. This confifts of fine threads, and is found on the italics of decayed fern and other vegetables. 8-. The purple bay-tree byjfus of Micheli. This is compofed of fhort interwoven fibres, and is common in Italy on the bark of the bay-tree. 9. The flaky fnow byjfus. This is defcribed by fome under the name of a white branched fungus. It is common in damp cellars, and fpreads itfelf to a great extent. 10. The hairy-fkinned byjfus. This grows in the manner of fome of the cruitaceous lichens on the bark of old trees, and is white and membranaceous on the under-fide, and all over hoary on the upper furface. 1 r. The black filky byffus. This is compofed of fhort filaments, fomefingle, others bifid, and is. found on the barks of old trees in many places. 12. The moufe-fkin cafk byjfus. This is common on old wine cafks, and is of a' tough cloth-like ftruc- ture, and greenifh black colour. 1 3. The yellow cloth lyjfus. This grows on the barks of old trees, and fomewhat refembles the. former in texture. 14. The green velvet-ground ty/for. This is common on the furface of the earth, in woods and on garden walks. 15. The elegant branching hairy byffus. This, from a hairy bafis, fends out a number of brandies, which fpread themfelves everyway, and fometimes divide at the extremities ' into fmall filaments, and femeti rhes form flat maffes. It is fome- times white, fometimes blueifh, fometimes yellowifb, and al- ways lies very clofe upon the things it grows from, which are rotten wood, decayed leaves, &c. 16. The faffron -co loured' rock byjfus. This is compofed of hairy globules, and grows on ftones. 17. The redifh hairy wood byffus. This grows on old boards. 1 8. The black haired rock byjfus. This is com- pofed of very fhort and very thick tufted filaments. 19. The red beard wood byjfus. This is compofed of very clofc-fef. hairs, and grows to half an inch in height. It is found on old rotten wood. 20. The whitifh briftly byffus. This is com- pofed of fingle and very ftiff briftles, of a whitifh colour, and about half an inch in length, and grows on ftones and old walls. Dillen. Hiit. Mule, p. 1 — ic.
c.
