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sn inch takes them up commonly between one and two 

 hours. He obferves alfo, that many of the fpccics have no 

 property of llinging, or caufing any painful fenfation on the 

 flelh. 



Dr. Gaertner obferves, that there is not a fmgle fpecies 

 of tlie urtica marina poHelTed of that flinging quality which 

 the ancients afcribed to them ; their tentacula indeed feel 

 rough and clammy, when touched with the finger ; but this 

 roughnefs is not perceptible, except when the animal at- 

 tempts to lay hold of the finger ; in which cafe it throws 

 out of the whole furface of the feeler a number of ex- 

 tremely minute fuckers, which, fticking fall to the fmall 

 protuberances of the (Icin, produce the fenfation of a rough- 

 nefs, which is fo far from being painful, that it even cannot 

 be called difagreeable. 



Thefe creatures occafionally change their bodies into fo 

 many different forms, that there is no giving any defcription 

 of their figure. The mod natural and general fhape feemi 

 that of a truncated cone, the bafe of which is applied 

 to the rock ; but this bafe is often round, often elliptic, and 

 often of a perfeftly irregular figure. The furtice of the 

 top of the cone is not flat, but convex, and has in its centre 

 an aperture, which the creature makes larger or fmalkr at 

 pleafure. In fome pofitions, the whole animal not unaptly re- 

 iembles a purfe, only with this difference, that the body is 

 not drawn up into any folds or wrinkles by the clofing of 

 the aperture or mouth. In the middle of this purfe, as we 

 call it, is placed the body of the creature, touching this outer 

 covering at the bottom on every fide, and of a conic fij^nrc, 

 as that is. At its top, however, it is loofe, and (lands 

 every way free from its covering ; the fides are more or Icfs 

 diilant from this free or loofe part of the body, as the aper- 

 ture at the top of the cone is more or Icfs open ; when it is 

 nearly fhut up, very little of the body of the animal can be 

 feen ; but when it opens into different widths, more or lefs 

 of the body becomes vifible ; and when it is at the widcll, 

 every part of it, and all the horns, are feen perfeftly dif- 

 tinft. Thefe horns refemble in appearance thofe of the 

 common fnail ; but in their ufe they feem much more allied 

 to the pipes or probofcides of the chamoe kind, the annnal 

 generally throwing out water at them on being touched. 

 They are placed in three ranges on the internal furface of 

 the covering, and are very numerous, their whole number 

 not being lefs than a hundred and fifty. 



The creature very often not only opens the outer cover- 

 ing or purfe to the utmoll width it is capable of, but at the 

 fame time turns back its extremities : in this cafe, the in- 

 ternal part, or body, becomes vifible on the furface, and 

 at the fame time all the horns being, by this bending back 

 of the fl<in on wliich they grow, thrown into the polhire of 

 fo many rays, the whole makes a very remarkable figure, 

 and not unaptly refemblcs an anemony, or fome other fuch 

 flower, when fully open. Very often alfo there is a great 

 addition to the beauty of this appearance, by feveral round 

 veficks of water, which appear blue, or of fome other lively 

 colour. The general colour of the different fpecies of this ani- 

 mal, or indeed of the fame fpecirs in diiferent circumllances, 

 is as variable as the (liape ; fometimes they are feen pellucid 

 and colourlefs, fometimes white, often yellowilh, lometimes 

 of a rofe colour ; at other times, they are of a beautiful 

 green, and often of various fhades of brown. In fome, thefe 

 colours are equally dilfufed through every part ; in others, 

 they are only feen in form of fpots and clouds, or variega- 

 tions ; fometimes thefe are irregularly difpof^-d, fometimes 

 more regularly, but always with great beauty. The green 

 ones have ufually a broad hue of blue all round their bafe. 



Neither the colour nor fhapes of thefe animals can be any 

 marks of different fpecies ; but the firmnefs of their flefh 

 may : in this they remarkably differ one from another, and 

 this is a difference the more obvious, as their flefh is always 

 open to the touch, there being no fhell, nor any other hard 

 fubfl;ance to cover it. However flow the progreflive motion of 

 this creature is, when examined it is found to depend on a very 

 remarkable mechanifm, to underlland which we mufl atten- 

 tively confider what is obvious to the eye in the ftrufture of 

 the creature, and remember the comparifon of the whole 

 to a purfe. We find that what refemblcs the bottom of 

 that purfe is flat, and is fixed to the rock, while the body 

 is contained in the red of the purfe, but never fills 

 it, unlefs when the mouth of the purfe or covering is clofe 

 drawn together. The whole covering is a coUeftion of muf- 

 cles, which are all tubular. The bafe of the animal never 

 appears to us, becaufe always fixed down to the rock ; but 

 when the creature is raifed from that pofition, and the bafe 

 examined, it appears compofed of a vafl number of tubes 

 placed one behind another, and running from the centre to 

 the circumference. Thefe tubes are often filled with an 

 aqueous liquor, which may be forced out on preffing them. 

 Befides thefe tubes, there are alfo many circular ones fur- 

 rounding one another. 



The progreflive motion feems to be thus performed : 

 when the creature has determined which way it will march, 

 it dillcnds all thofe longitudinal tubes which are on that fide 

 of its body which is placed toward the point it would move 

 to ; tlii.s, from its round fhape at the bafe, gives it an oblong 

 one ; that is, it throws the fore-part fomewhat forward upon 

 the rock ; and, at the fame time, if the longitudinal tubes 

 on the oppofite fide of the body be all left empty, and the 

 circular ones diftended, thefe naturally draw the whole body 

 toward the fore-part, and thus a fmall advance is made and 

 prefervcd, and this, often repeated, is the flow progreflion 

 of this animal. AH this is, however, performed fo very 

 flowly, that though there is a continual change going on in 

 the creature, both as to fliape and place, yut it the eye is 

 kept continually on the object, neither is perceived ; but if 

 taken off for fome time, and the place and figure both kept 

 in mind, both will be found to be altered on viewing again. 



There is a fpecies of this animal alfo which moves by means 

 of its horns ; this is known from the reft by the length of 

 the horns, and their being covered with a glutinous moifture. 

 This fpecies lives in the cavities and holes of rocks ; and 

 when it has a mind to move, it turns itfelf bottom upwards, 

 and crawls flowly on by means of its horns, which then 

 touch the rock. 



The food of the urtica marina is not lefs wonderful than 

 its ftruclure and motions. It fliould feem very ftrangc that 

 an animal, foft like this creature, with no feet nor inttru- 

 merit of that kind to help itfelf with, fhould be .ible to feed 

 on tho flefh of mufcles, fea-fnails, and other fliell-fifli ; yet 

 thefe are its conflant food. They find means to take in the 

 fliell-fifli whole into the body, and then clofe the aperture 

 fall upon it, fo that it is not to be feen that they h.ive any 

 fuch thing within them ; they keep them here as long as 

 t!iey pleafe, and afterwards throw out the empty fliells by 

 the fame aperture, wiiich they can, as before obferved, widen 

 and contrail at pleafure. By what menus the urtica is able 

 to get out the body of thefe lifh, is not known, as it all 

 pafl'es in the body ; but it very often fails, and the crcatiire 

 is obliged to throw out the fliell-filh alive ag.iin ; and fome- 

 times when it has greedily gorged too large a morfcl, and it 

 is got into a wrong pofition to be thrown out the fame way, 

 it 19 obliged to let it tlirough the bafe, where there is no 



natural 



