Introduction. 



We had alfo an Opportunity of feeing thofe Corallines in 

 Motion, whofe Polypes are contained in Cups, fupportcd by 

 a long Stem that appears full of Rings, or as if they were 

 tvvifted in Form of a Screw (See Fig. C, Plate Xil). In 

 the Middle of the tranfparent Stems or Cafes, we could eafily 

 diftinguilli the Thread-like tender Part of the Animal, united 

 to the Bottom of each Polype. 



As we were obferving this, we accidentally difcovered the 

 Figure of the Polype, that fpreads its Cells ov^r Fucuss^ and 

 other Marine Subftances. The Figures of the Cells are ex- 

 prefled in Plate XXIX, at Letter D. And the Animal in 

 its Cell at Z) I. 



On feveral Parts of thefe CoraUines there are little Bodies, 

 which, through the Microfcope, appear to be fo many Ve- 

 ficles or Bladders : To the Ufe of thefe I was altogether a 

 Stranger till this Journey : But now I difcovered that they 

 were Matrices^ or Habitations of young Polypes, which are 

 produced here and there, on the Sides of the Parent, as in 

 the Frefh-water Polype, only in the marine ones they are 

 protected with this veficular Covering. Thefe Veficles ap- 

 pearing at a certain Seafon of the Year, according to the 

 different Species of Corallines, and then falling off, like the 

 Bloffoms or Seeds of Plants, has made fome curious Perfons, 

 who have not had an Opportunity of feeii^.g the Animals alive 

 in the Veficles, conclude them to be the Seed-veflels of Plants ; 

 and into this Miftake I was led myfelf, in the Account laid 

 before the Royal Society in 1752. In which Account I had 

 taken fome Pains to point out the great Similitude between 

 the Veficles, and denticulated Appearance of fome of thefe 

 Corallines ; and the Tooth-fhaped Leaves and Seed-veffels 

 of fome Species of Land-moffes, particularly of the Hypnum 



b and 



IX 



