198 TOILERS IN THE SEA. 



semi-transparent flower, having eight petals fixed 

 upon a mammal bud; when closed they have the 

 appearance of an urn." 1 It will be observed that 

 the red coral differs considerably in its animals from 

 the corals of the coral reefs. In the latter case the 

 animals are either of the Anemone type, or what are 

 termed in scientific language Actinoid polyps, or, as 

 in the Millepores, of the hydroid type ; whereas in 

 the red coral they are of the type which prevails in 

 " dead man's fingers," and the " sea-fans," that is of 

 the Alcyonoid type, hence " precious coral " is more 

 nearly related, in its structure, to the Gorgonias than 

 to the rock corals. Probably the general reader will 

 not at once appreciate the differences, or their 

 importance, so readily as the zoologist, although we 

 have placed them in different chapters in this volume, 

 in order to emphasise that difference and prevent 

 the confusion of the two kinds of substance to which 

 the name of " coral " has been given. 



The structure, and reproduction, of the red-coral 

 polyp has been studied more exhaustively b} 

 M. Lacaze-Duthiers than by any one else, before 

 or since, and a summary of the facts which he has 

 made known will be of interest, to compare with 

 those we have given elsewhere of the rock corals. 



1 Moquin-Tandon : "The World of the Sea," London, 1869, 

 p. 109. 



