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in autaiTui, in woods, upon rotten wood, mofles, &c It 



forms denfe tufts, each plant the fize of garden poppy-feed, 

 and burfting in an irregularly circular manner, near the top. 

 This is one of our moft frequent fpecies. 



7. T. olivacea. Perf. Obf. Mycol. fafc. I. 62 



Scattered, feflile, roundifli, or obovate, abrupt at the bafe, 

 olive-coloured. Internal hairs compaft, yellowiih. — Found 

 rarely on the ftems of trees. Hc-aJs globular, or hemi- 

 fpherical, becoming by mutual prefTure, when crowded, 

 oblong, or fomewhat cylindrical. Perfoon is doubtful whe- 

 ther this be a diitinft fpecies. We have feen no fpecimen. 



Seft. 2. Head round, or kidney-Jhaped. 



8. T. n'ltens. Perf. Obf. Mycol. fafc. i. 62. (" Lyco- 

 perdon favogineum ; Batfch Elench. Fung. 257. t. 173.") 

 — Crowded, fefTile, globular, of a (hining yellow or cinna- 

 mon-colour. — Found in autumn, about the decaying trunks 

 of fir-trees, as well as on beeches. In the former cafe it is 

 more opaque ; in the latter more bright and fhining. The 

 head is occafionally a little turbinate. 



9. T. varia. Perf. Obf. Mycol. fafc. 2. 32. (Lyco- 

 ga3a luteum, omnium minimum, reniforme ; Mich. Nov. 

 Gen. 216. t. 95. f. 4.) — Rather crowded, yellowi(h, partly 

 deflexed. Head kidney-fhaped, roundifh, or fomewhat ob- 

 long — Grows on rotten trees in autumn. Found by 

 Micheli in the celebrated gardens of Boboli, behind the 

 palace Pitti, at Florence. He reprefents it as forming 

 globular maffes, the fize of a large pea, each plant fmaller 

 than poppy- feed. The lateral ones appear to be deflexed, 

 or forced outward, by thofe in the middle. 



Seft. 3. Receptacle elongated, thread-Jhaped, creeping, 

 Jtrnple, or interhranch'mg I'the veins. 



10. T. Serpula. " Perf. Difp. Meth. 10." (Mucor 

 Serpula ; Scop. Cam. 493. t. 65.) — Thread-ftiaped, un- 



branched, very long, fomewhat zigzag, yellow On the 



trunks of trees in Carniola, near the roots. Scopoli. This 

 is reprefented as a fmooth yellowiih thread, creeping like a 

 Serpula, or Worm-fhell, and refembling a fmall animal in- 

 teftine. It burfts and difcharges, from every part, tufts of 

 fine hairs befprinkled with yellow powder. Scopoli. T. Jpon- 

 gioides, Villars Dauph. v. 3. 106 1, is thought by Perfoon to 

 be a variety of this. But the author's defcription of " from 

 three to five little oblong, cylindrical, worm-like bodies, 

 vvhofe yellowiih internal woolly fubftance foon confounds 

 them in one woolly mafs," indicates rather fome of the 

 former feftions, or perhaps an Arcyria. 



1 1. T. reticidata. " Perf. Ic. et Defer. Fung. fafc. 2. 46. 

 t. 12. f. I." (Lycoperdon lumbricale ; " Batfch Elench. 

 Fung. 259. t. 30. f. 174." Willd. Berol. 414.) — Thread- 

 fiiaped, branched, reticulated, yellow. — Found in autumn 

 on the trunks and mofly bark of trees, but very rarely. We 

 have never heard of this or the preceding in Britain. The 

 prefent fpecies is defcribed as fpreading to the extent of an 

 inch, confifting of a yellow net-work, burfting here and 

 there, and protruding tufts of yellow hairs, enveloping a 

 powder, or feeds, of the fame colour. 



It will readily be perceived that the fpecies of this genus, 

 however curious, can, as yet, be but imperfe<Etly defined ; 

 nor are we certain how far the Arcyria, Stemonitis, Cri- 

 braria, &c. of Perfoon are entitled to rank as generically 

 diftinft. 



TRICHIASIS, (derived from Sf if, /*?*«!>,) mSurgery, 

 fometimes alfo named enfropeon, denotes a faulty inclination 

 of the eye-lalhes inwards againfl: the globe of the eye. Ac- 

 cording , J Scarpa, the difeafe prefents itfclf under two diftinCl 

 forms : the firft is, where the cilia are turned inwards, with- 

 out the natural pofition and direftion of the tarfus being at 

 all changed ; the fecond confifts in a morbid inclination of 



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the tarfus, and confequently of the eye-lafh towards the ball 

 of the eye. 



The firft form of this difeafe is very rare, nor has it come 

 under the obfervation of the experienced Scarpa more than 

 once ; and in this inftance, only fome of the hairs had changed 

 their direftion. The fecond fpecies or form of trichiaiis, 

 or that which confifts in a folding inwards of the tarfus and 

 cilia at the fame time, is that which is commonly met with 

 in praftice. This may be either complete, affefting the 

 whole of the tarfus ; or incomplete, occupying only a cer- 

 tain portion of the edge of the eye-lid, and moft frequently 

 near the external angle of the eye. Sometimes the difeafe 

 is confined to one eye-hd ; at other times it affefts both ; and 

 occafionally the patient is afflifted with it in both eyes. 



To thefe two fpecies of trichiafis, fome writers have added 

 a third, which they call dijlichiajis, and which they fuppofe 

 to be produced by a double and unufual row of hairs. But 

 this third fpecies, as Scarpa obferves, is only imaginary, and 

 the reafon of fuoh fubdivifion feems to have arifen from 

 not recollefting what was long ago remarked by Winflow 

 and Albinus, that although the roots of the ciha appear to 

 be difpofed in one hne only, they neverthelefs form two, 

 three, and in the upper eye-lid even four rows of hairs, 

 unequally fituated, and as it were confufed. Whenever, 

 therefore, in confequence of difeafe, a certain number of 

 hairs are feparated from each other in a contrary direftion 

 and diforderly manner, the eye-lani will appear to be com- 

 pofed of a new and unufual row of them, wliile, in faft, 

 there has been no change, either with refpcft to their 

 number or natural implantation. 



It is not an eafy matter to determine precifely, fays 

 Scarpa, what are the caufes which fometimes make a few 

 of the hairs deviate from their natural direftion, while the 

 tarfus continues in its right pofition. They are commonly 

 referred to cicatrices in confequence of previous ulceration, 

 whereby the cilia fall off, and thofe which are growing are 

 hindered from taking their proper direftion. There muft, 

 however, be other caufes fometimes concerned; for in the 

 cafe feen by profeffor Scarpa, two or three hairs were 

 turned inwards againft the eye-ball, although there had been 

 no preceding ulceration, nor cicatrices of any part of the 

 tarfus. Indeed Scarpa is inclined to beheve, that the fmall 

 ulcers and fears which are fometimes formed upon the internal 

 margin of the tarfus, are more likely to produce the fecond 

 form of the difeafe, or the inverfion of the edge of the eye- 

 lid, and confequently of the cilia towards the globe of the 

 eye. As thefe ulcers, when neglefted, deftroy the internal 

 membrane of the eye-lids near the tarfus, it neceffafily 

 follows, that in proportion as they heal and diminifh, they 

 draw along with them and turn inwards the tarfus, and hairs 

 inferted into it. And fince thefe little ulcerations do not 

 always occupy the whole extent of the internal margin of 

 the eye-hd, but are fometimes confined to a few lines, in th« 

 middle or extremity, near the external angle of the eye -lid \ 

 fo after the cicatrices are formed, the whole of the hairs are 

 not invariably turned inwards, but only a certain number of 

 them, which correfpond to the extent of the ulcers previoufly 

 fituated along the internal edge of the tarfus. Indeed, in 

 every cafe of imperfeft trichiafis from a cicatrix of the inner 

 margin of the eye-lid, the tarfus and cilia are every where in 

 their natural fituation, except oppofite the part where the 

 ulcers formerly exifted. Alfo, if the eye-hd be everted, 

 its internal membrane, near that part of the margin corre- 

 fponding to the feat of the trichiafis, will be found pale, rigid, 

 and hardened, the inverfion of its cartilaginous border and of 

 the ciha being plainly a confequence of the contraftioQ of 



the cicatrized point. „ , , 



E e z Befidcs 



