72 OFSTONES. 



gated with a purplifh-red, under a thin cuticula, or crufl of the 

 fame colour, part of which is taken off by politure to mew its 

 elegant ftructure and beauty, the variegated circles very much 

 refembling fmall flowers. From the fhore of the brook below 



1 8. A marmorite compofed of fine capillary filaments, lying 

 in various directions, fome of them forming beautiful dendntf y 

 or arbufcular figures, of a fan-like fhape, of two different de- 

 grees of purple, with a flight tinge of orange and carmine ; ca- 

 pable of an excellent polifh. From the fhore of the brook at 

 G of ton, near JYark, in Tynedale. 



19. A marmorite of the fame ftruclure, of a grey colour, of 

 two different degrees ; the fine forming a large radiated figure 

 at one end, refembling the rifing Sun. From the fhore of the 

 brook at Simonburn, near the fchool-houfe. 



We have a variety of it with tranfverfe femicircular fillets, of 

 a light grey, on a dark grey ground. It is more frequent with- 

 out thefe elegant figures, yet very beautiful, the ends of the fila- 

 ments forming a curious reticular work ; its general colour grey, 

 lighter or deeper, arid fometimes of both thefe colours, in 

 clouds and variegations. 



20. A marmorite formed of a congeries of aflroite coralloids, 

 of a button-like fhape, of a greyifh-black colour, with black 

 maihes. From the more of North Tyne, oppofite to Kirk-feld, near 

 Wark y in Tynedale. 



Thefe rnarmoreous Fibrari<e all ferment violently with acids. 

 They are of a marine origin, and are commonly found en- 



tombed 



