FOSSIL CORALS. 



59 



They are compound corals, whose shapes are modified 

 by the manner in which they grew, so that some are 

 polygonal, or many-sided, and others oval or round. 



I' is- 2,7- — Syi-'ingipora 7-anuihsa, a common Carboniferous limestone Coral. 



The most remarkable of these tabulate fossil corals 

 are Heliolites, Favosites^ the pretty " chain-coral " 



Fig. i^.—IIdiopora ca-ruZca, a recent Alcyonarian Coral. 



(Halysites)^ Syringipora^ etd. It will be seen from 

 Fig. 36, which shows a magnified section of a very 



