154 CORALS 



Good Hope. As in Stylaster, both the gasteropores and 

 the dactylopores are provided with styles, but the caHces 

 are not so prominent, the ampullae are inconspicuous, and 

 the terminal branches relatively thick and blunt. 



AUopora nohilis of the Cape is the largest and most 



I'lG. 72. — Stylaster. A small part of a branch highly magiiitifd to show the 

 cyclo-systt'ins. Note the styles in the centrally placed gastcropore and in the 

 surrounding dactylopores. x 20 diams. 



robust of all the Stylasterina. It seems to construct great 

 submarine forests in some localities which effectually pre- 

 vent successful dredging, as the great solid stems, over an 

 inch in diameter, are firmly fixed to rocks on the bottom. 

 Errina.^ — Of the remaining genera, Errina, with its 



' S. J. Hickson, " The genus Errina," Proc. Zool. Soc, igi2, p. 876. 



