HOLOTHURIA. 



141 



Sea-egg. All these creatures are called by the 

 general name of Uchinodermata, signifying 

 "urchin-skinned." We have already seen how 

 great is the apparent distinction between the 

 several creatures that are classed together under 

 this title, and this outward distinction is quite 

 as great in the last example that will be here 

 mentioned. 



There is a curiously-shaped creature repre- 

 sented on plate f, fig. 6, looking something like 

 a cucumber, with a feathery fringe attached to 

 one of its ends. This is popularly called, on 

 account of its shape, the Sea-cucumber, and is 

 scientifically termed Holothuria, The derivation 

 of the word is Greek, but its signification is very 

 uncertain. It was used by Aristotle in his " His- 

 tory of Animals;" but the reason why he so 

 named the creature no one can tell. 



The holothurisD are very curious creatures, for 

 they possess some organs of the Echinodermata, 

 by virtue of which they rank as Echinoderms, 

 and they also have other organs, which seem to 

 imply a connexion with the sea-anemones, while 

 the shape somewhat approximates to the annulate 

 form of the worms. Like the star-fishes and the 

 Echinus, they possess five rows of sucker-feet 

 along the body, although in some species these 



