RADIATA. 37 



P. grisea^ Esper {fig. 27), inhabit the Mediterranean ; Yirgula/ria juncea., 

 Esper {fig. 24), Europe. 



Fam. 2. AlcyonidoB. Fleshy, with calcareous granules, Alcij07iiitm 

 ficiforme {pi. 75, fig. 46), size and shape of a fig, and of a jellowish- 

 brown color; and A.palmatum {fig. A:1)., stem divided irregularly, some- 

 what like a hand ; pale-red. Mediterranean. 



Fam. 3. CornularidcB. With corneous tubular coralla. 



Fam. 4. TuhiporidcB. With calcareous tubular coralla. Tuhipora 

 musica {pi. 75, fig. QQ) is of a fine red color, the body green. Indian seas* 



Fam. 5. GorgonidiE. With basal epidermic secretions. Gorgonia 

 fluhellum' {pi. 75, fig. 48). Eeticulate, branches inwardly' compressed ; 

 three feet long. Warm seas of India and America. G. verrucosa^ Linn. 

 {pi. 75, fig. 49). Atlantic, six to twelve inches. G. ceratopkyta {fig. 50), 

 Mediterranean. Isis hipptiris, Linn. {fig. 53); stem jointed and strong, 

 branches dichotomous. East Indies. Coralium nobile., Linn. {pi. 75, 

 fig. 52), is branched, one foot high, varies from a fine deep-red to a rose 

 color, or white with a reddish tinge. It admits of a fine polish, and is 

 much, used for light ornamental work. When fresh, the^xterior is fieshy 

 and polypiferous, which, in drying, forms a crust with scattered cellules. 



The forms of the corals which most of the zoophyta secrete, are extremely 

 varied ; representing various plants and mosses, variously shaped vessels, 

 domes, obelisks, radiated disks, leaves, &c. ; and the size of the coral mass 

 varies from a few lines to twelve or even twenty feet. The large masses 

 have commenced in a single animal, from the successive budding of which, 

 the whole has resulted. 



" Calculating the number of polyps that are united in a single Astrrea 

 dome of twelve feet diameter, each covering a square half inch, we find it 

 exceeding 100,000 ; and in a Porites of the same dimensions, in which the 

 animals are under a line in breadth, the number exceeds five and a half 

 millions. There are here, consequently, five and a half millions of mouths 

 and stomachs to a single zoophyte, contributing together to the growth of 

 the mass, by eating, and growing, and budding, and connected with one 

 another by their lateral tissues and an imperfect cellular or lacunal com- 

 munication." — Dana^ p. 60. 



In those cases where single polyps occupy the extremity of dead branching 

 stems, there is no union of the soft parts of dififerent individuals. 



Glass 3. Echinodermata. 

 The Echinodermata, which are all marine, and include what are popularly 

 termed star-fish, sea eggs, &c., are the most highly organized class in the 

 radiated division of the animal kingdom. The bodies of some are raised upon 

 a pedicle, the base of which is fixed to a single place ; others are without a 

 pedicle, and move freely and slowly along the bottom. Some of the latter 

 are provided with a multitude of sucker-like feet, which, in Asterias 

 auranUaca^ amount to 840, according to Tiedemann. Some are provided 

 with eye dots, which, in Asterias, &c., are situated at the extremity of the 

 rays ; and where the nervous system has been detected, it forms a circle 



ICONOGRAPHIC ENCYCLOPEDIA. VOL. 11. 16 241 



