CORALL1FEHI. 491 



GORGONIA, Linnaeus, 



Where, on the contrary, this horny or ligneous substance of the axis is 

 enveloped by a bark, the thickness of which is so penetrated by calcareous 

 granules that it dries on the axis, retaining its colours, which are frequently 

 extremely vivid and beautiful; it is soluble in acids. The Polypi of several 

 species have been observed; each one is furnished with eight denticulated 

 arms, a stomach, &c., like those of Corallina and Alcyonium. 

 In the second tribe, that of the 



LlTHO'HYTA, 



The internal axis is of a strong substance and fixed. In 



Isis, Linnceus, 



This axis is ramous, and has no cells or cavities on its surface. The animal 

 bark which envelopes it is mixed with calcareous granules, as in the Gorgoniae. 

 In the 



MADREPORA, Linnceus, 



The stony portion of Madrepores is either ramous, or forms rounded 

 mosses, or leaves, but is always furnished with lamellae which unite concen- 

 trically in points where they represent stars, or which terminate in lines 

 more or less serpentine. While alive, this stony portion is covered with a 

 living bark, soft, gelatinous, and completely covered with rosettes of tentacula, 

 which are the Polypii or rather the Actiniae, for they usually have several 

 circles of tentacula, and the lamellae of the stars correspond in some respects 

 to the membranous laminae of the body of the Actinias. The bark and Polypi 

 contract on the slightest touch. 



The diversity of their general form, and of the figures which result from 

 the combination of their lamellae, has given rise to various subdivisions, 

 several of which however re-enter others. It will be impossible to establish 

 them definitively until the relation of the Polypi with those forms are 

 known. 



When there is but a single star, circular or in an elongated line, with very 

 numerous laminae, we have the FUNGIA, Lam. The animal exactly repre- 

 sents a single Actinia, with large and numerous tentacula, and of which the 

 mouth corresponds to the depressed part in which ah 1 the laminae terminate. 



Stony corals with a single star, that appear to have been perfectly free from 

 adhesion, are found among fossils, and constitute the TURBINOLIA, Lain., 

 CYCLOLITHUS, and TURBINOLOPSIS, Lamouroux. 



When the Madrepore is ramous, and the stars are confined to the extremity 

 of each branch, it becomes the CARYOPHYLLIA, Lam. The branches are 

 striated. At each star is a mouth surrounded with numerous tentacula. 



OCULINA, Lamarck. 



The Oculinae have very short lateral ramusculi, giving them the appearance 

 of having stars along the branches as well as at the end. In 



