134: ZOOPHYTES. 



These Zoophytes or Polyps, as they are also called, arc 

 of three kinds, viz. : 



1. Ilydraforms. Where each animal is solitary or joined 

 to a stem, common to a great many individuals ; and 

 the stem or " polyp-house," as it is called, is horny and 

 hollowed like a reed. 



2. Asteroids. Here the polyps are united in family like 

 those of the last division, but the "polyp-house" is fleshy, 

 and the polyps open on the surface like a star with six 

 or eight rays. 



3. Hdianthoids . — The polyps are here single or attached 

 temporarily or permanently to their dwelling places in the 

 rocks. Some few being " free," and some, c. g., corals sur- 

 rounded with a crust of hard lime — their tentacles (or 

 arms) open out in a circular form like the rays of the sun. 



All these three orders may be represented in an Aqua- 

 rium ; but the animals belonging to the last, Ilclianthoids, 

 are those that we shall be most likely to find, and are, 

 also, the most ornamental. The Zoophytes have a curious 

 property of bearing to be cut or torn into two or more 

 portions, without either portion dying therefrom. If we 

 sever a limb from the body of almost any other, animal, 

 it will not become a separate creature ; but if we cut a 

 Zoophyte in two, each piece will live and become an inde- 

 pendent and perfect existence. 



This curious property of bearing dismemberment, or seve- 

 rance, without any great inconvenience, can be proved, if 

 we wish to experiment with some of the fresh-water polyps, 

 which are more easily procurable to many persons than the 

 marine Zoophytes. In most brooks and ponds we find adher- 

 ing to stones, plants or dead leaves and, indeed, to any 



