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CHAPTER VIII. 
ALCYONARIA. 
** As for your pretty little seed-cups, or vases, they are a sweet confirmation of 
the pleasure Nature seems to take in superadding elegance of form to most of her 
works. How poor and bungling are all the imitations of art! When I have the 
pleasure of seeing you next, we shall sit down—nay, kneel down—and admire 
these things.” —HoGaRTH To ELLIs. 
Tue Alcyonaria are so designated from their principal type, that of 
Alcyonium. The species are all marine. The Alcyonaria may be 
defined as Actinozoa in which each polype is furnished with eight 
pinnately fringed tentacles. The chambers into which the body is 
divided are some multiple of four. The corallum is often dense, 
sometimes consisting, however, of calcareous spicules, and unlike 
that in the Zoantharia, never showing traces of septa. We shall see, 
farther on, that among the Gorgonide the coral ceases to be spongy 
and cellular; that its axis assumes a horny consistence, which be- 
comes often even stony; but the external barky layer, which is 
the special lodging of the polyps, always remains soft on the surface. 
We shall have a general idea of the organisation, habit, and mode of 
multiplication among the Alcyonaria when we come to treat of the 
precious coral and its strange history. The class Alcyonaria may be 
divided into many orders. We shall consider—I. The Zudiporide. 
Il. The Gorgonide. ITlI. The Pennatulide. IV. The Alcyonide. 
I. THE TUBIPORIDA 
form a group consisting of several species, which live in the bosom 
of tropical seas, in which the Coral Islands form so prominent a 
a feature. The group is exclusively formed of the curious genus 
Tubipora. 
The Zubipora is a calcareous coral, formed by a combination of 
distinct, regularly-arranged tubes, connected together at regular dis- 
tances by lamellar expansions of the same material. The aggregate 
formation resulting from this combination of tubes constitutes a 
variously-shaped mass, which often attains a very considerable size. 
