PETRIFACTIONS. 109. Helmintholithus* 345 



Isidis. The Ifis or Coral. 



1. The Ifis Hippuris, 



The fingle joints are often found in England, Switzerland zn^ 

 Sicily. 



2. The Tils Entrocha. 



Htlminth, Entrochites. Syst^ nat. Tin, '^. p 168, «, 17, 

 Aftcria columnaris. Harenb. encrin, t. i. f. S -10. 

 Entrochus. Folm. Sile/. i. tah. 27. fig. 9, 10. 



Found in England sind aim ft every par. of the continent, fome* 

 times in lingls feparate joints, fometimes connefted together 

 into a column, from the fize of a pin's head to a finger's 

 length and the thicknefs of the middle-finger: they are !• ore 

 or Icfs tranfparent in proportion as they contain more or lefs 

 filiea, are ftriated from the centre to the circumference and 

 have a cavity in the middle. When powdered they are ef- 

 teemed very powerful diurfticf, and are exhibited in nephri- 

 tic cafes ; the dofe being ab much as will lie on a Ihilling, 



a. Smooth, with the margin nearlv entire. 



b. Smooth, with the margin undulately fcalloped, 



c. W^rty* 



d. Prickly^ 



e. DotteJ. 



f. Tranfverfely ftriate. 



g. With the joints elevated. 



h. Branched in a forked manner. 



3. The Madrepora Afteria. ^tar-flone^ 



a. With the angles more or lefs obtufe. 



He minthol. Alleria. '^yft. nat xii. 3.^. 168. «. i8. 

 Modiolus fteilatus. Scheuch. Hel'V, 10 fig^ 3, 

 Modiolus ftellatus. Lang. fig. by tab,\(^.f, 2, 

 Afteria pentagona Rofin Hell 35, tab. 5. 

 Afteria column a. Gefnerfig 37. Volkm/jllef^ttZ'j, f^2t, 

 Lluydlithop. Brit, tab. I 3, 22. 



b. With the angles acute. I 

 Helminthol Stella Syft nat»m\. 3. ^. 169, »« 19. 



Lapis jud^icus. Wagn. Judaic, 1 1. Jig, 27. 



c. Orbicular. 



d. Oroicular at one end and angular at the other. 



VOL. Vll, — X X 



