22 Natural Hiftory of 



Stalks divided into Joints by fmall Rings ; from thefe pro- 

 ceed little Footftalks twifted like a Screw, that fupport Vefi- 

 cles of an oval Shape ; fome with a fmall Opening at the Top, 

 and fome quite open. This is found in great Abundance on 

 the South-Weft Coaft of Englandy and feems moft curioufly 

 contrived, from its Structure, to refift the Violence of the 

 Waves, all its Joints being furnifhed with Springs. Its Veficles 

 are alfo formed fo as to yield eafily to every violent Impulfe 

 of the W^ater without Injury, from their being placed on Foot- 

 ftalks formed like Screws. 



Fig. a, N". 1 8. in Plate XII. is the Appearance they make 

 in their natural Size. 



Fig. Aj ftiews Part of a Branch magnified. 



Plate XII. •^''' ^ 9* Corallina minor repens caule nodofo^ articulator ^ 

 Fig. t. B. veficulis alter?iis ijiJiruEio. 



Knotted-thread Coralline. 



This creeping Coralline is generally found adhering to the 

 podded Fucus, from whence it throws out little jointed and 

 waved tender Branches, about an Inch long : The upper Part 

 of the Joints appear to be knobbed ; upon thefe reft the Veft- 

 cles in an alternate Order, fupported by fcrew-like Footftalks. 

 The Shape of the Veficles is like an Oil- Jar with a Neck to it. 



This Coralline was found at Dover ; and I have lately re- 

 ceived fome Specimens from Harwich ; fo that I believe it is 

 not uncommon on our Coafts. 



Fig. ^, N". 19. Plate XII. was drawn from a fmall Piece of 

 the podded Fucus^ with feveral Branches of this Coralline 

 growing upon it. 



Fig. Bj gives the Appearance of a fmall Branch of it mag- 

 nified. 



In 



