CORALLIFERI. 435 



are very numerous in fresh water, and arc generally to small to be 

 perceived without a microscope. They form bushes, arbuscles. 

 Illumes, &c. &c. *. 



Pedicellaria. 

 The Pcdicellarire are found between the spines of the Echini, and 

 are considered by various authors as organs of tlicse animals ; most 

 probably however they arc Polypi, which there seek an asylum. 

 Tliey consist of a long slender stem, which terminates by a horn, 

 furnished at its extremity with tentacula, sometimes filiform and 

 sometimes foliaceous f- 



ORDER III. 



CORALLIFERI (a). 



The Coralliferi constitute that numerous suite of species which 

 were long considered as marine plants, and of which the individuals 

 are in fact united in great numbers to constitute compound animals , 

 mostly fixed like plants, either forming a stem or simple expansions, 

 by means of a solid internal substance. The individual animals, 

 more or less analogous to the Actiniae or Hydrae, are all connected 

 by a common body, and are nourished in common, so that what is 

 eaten by one goes to the nutrition of the general body, and of the 

 other Polypi. Their volition is even in common, at least it is cer- 

 tainly so in the free species, such as the Pennatulae, which are seen 

 swimming by the contractions of their stems, and the combined mo- 

 tions of their Polypi. 



The name of Pohjpicrs has been given to the common parts of 

 these compound animals ; they are always formed by deposition, and 

 in layers like the ivory of teeth, but are sometimes on the surface, 

 and sometimes in the interior of the compound animal. This dif- 

 ference of position has given rise to the following families. 



* The only species I refer to this genus are those figured in the Encyc., pi. 

 XXIV and XXVI. They are closely united by strong affinities with certain species 

 placed among the microscopical animals. 



t MiilL, Zool. Dan., XVI, copied Encyc., LXVI, 



(j:^ («) The Polypes a Polvpiers of onr author. Here is another instance of 

 the many difficulties we have had to encounter in the course of this work, and of the 

 impropriety of the attempts to establish the use of French terms in the Sciences, now 

 being made, notwithstanding the inconvenience, confusion, and error they are sure 

 to produce. 



The term pohjiner, for which we have no adequate word, has lately been coined to 

 express the common part of these compound animals, or the sxibstance we usually 

 denominate Coral — CoralHum — and as it is an excretion, wc have ventured to ren- 

 der Polypes d Pohjpievs by Polypi cvraUiferi, and the term Polypiers by the word 

 coral. — Eng. Ed. 



