FOSSIL CORALS. 



^3 



group these objects, along with others similarly star- 

 rayed in their shapes, into the sub-kingdom Radiata, 

 now no longer accepted by naturalists. In this 

 radiated structure, therefore, the rugose corals re- 



SJ\ 







Fig. 42. — Horizontal section across block containing 

 Lithostrotion jwicetim (.Carboniferous limestone).' 



Fig. 43. — Vertical section oi Lithostrotion Fig. ^^.—Amplexus corallotdes 

 jwiceziin, (Carboniferous limestone). 



semble the aporose corals. But whereas the tabulate 

 and rugose corals (with few exceptions) are limited 

 to Palaeozoic rocks, the aporose corals are peculiar to 



