iS6 



AN- INTRODUCTION TO ZOOLOGY. 



In the English sea the Zoantharia are chiefly re- 

 presented by the common sea-anemones {Aatinim), 

 which are single polyps with no skeleton. Their 

 flower-like appearance has given them their name, 

 many of the species being beautifully coloured. One 

 of the finest, known as the Dahlia anemone, is banded 

 with bright crimson and attains a very large size, 

 often considerably exceeding that of the flower it is 

 supposed to resemble. The common coral of the Eng- 



Fig, 33. — Mushroom coral, Funqia : a, view from above ; h. Bide view. 



lish seas is the Cup-coral {Oari/ophyllia), which is a 

 polyp much like the sea-anemone, but secretes a hard 

 coral. The majority of the showy corals brought from 

 abroad, such as the Brain-stone corals and Mushroom 

 corals, belong also to this order. 



In the Madrepores {Zoantharia), the " coral " or 

 calcareous skeleton is secreted by the outer layer of 

 the body (ectoderm), folds of which project inwards 

 into the chambers between the mesenteries, pushing 

 the two other layers in front of them ; in these folds 



