( f^T ) 



ANTIIn/(».\. 



The existing Anthozou ai'e cunstructt-d ou diic of two tyiMrs ; 

 they either have eight tentacles and no more, or, like the eouimou 

 Sea-Anemone, they have a number of tentacles. Where there arc 

 only eight tentacles, as in the noble red coral, each is fringed at its 

 sides, or, in technical terms, is pinnate ; when the tentacles are 

 numerous they are non-pinnate. A certain number of iwilaeozoic 

 corals had a symmetry of four, ^^'e may therefore speak of Tetra- 

 coralla,^ Hexacoralla,'^ and Octocoralla.^ 



Both of tlie latter may have (i.) soft bodies without si)icule.s, (ii.) 

 horuy axes (horny corals), (iii.) a continuous limestone skeleton 

 (stony corals) ; the Alcyouaria may have scattered spicules. 



The Hexacoralla, or Zoautharia, commence at the eastern end of 

 the Gallery, next the Hydrozoa ; the Octocoralla, or Aleyonaria. 

 commence at the western end of the Gallery. 



The organisation of the Alcyonaria is illustrated by lars^e 

 diagrams ; the first, that of Moiuu-enid danrini, is very possijjly ludy 

 a larval stage of some Alcyouarian ; Ijut it shows some of the 

 essential characters of the group. These are a sac-like Itody, with 

 an axial gastric cavity, giving oft" eight compartments, on the 

 partition walls of which are developed the gonads or reprtKluctive 

 elements. 



The organism seldom remains single ; developing a .stolon or 

 creeping process, it gives rise to bud after bud, and so forms a 

 colony, as in Clavulffria (Figs. 1 and 2) or Alri/o/iiiun (Fig. ;{). 

 diagrams of whicli are shown. There arc also some excellent wau-r- 

 colour sketches of Clavulariaus taken from life, and presented by 

 Prof. Ilicksou, F.R.S. 



The creeping process or stolon is well seen in tlie small i.rei>a- 

 ratiou of the organ-pipe coral {Titbqiora) ; as shown in Fig. I, this 

 is seen to be a small flat plate, from which ihe tulM?s are beginuiui? 

 to rise up. 



' Sivc Rugosa. * Sivc Zoantharia. ' '^"'■' M.-V'-muhi. 



