54 



ANTHOZOA. 



walls of the cyst (12, 13, 14, 15, 16) and soon developes itself ^ into an 

 Aspidiscus. How the Aspidiscus returns to the Oxytricha-form is still 

 a matter for speculation. 



CHAPTER IV. 



ANTHOZOA. 



ZOOPHYTES of old Authors. PIIYTOZOA (Ehrenberg). 



(111.) IT is not surprising that many members of the extensive 

 class upon a consideration of which we are now entering should have 

 been regarded by the earlier naturalists as belonging to the vegetable 

 kingdom, with which, in outward appearance at least, numerous species 

 have many characters in common. 



(112.) Fixed in large arborescent masses to the rocks of tropical 

 seas, or, in our own climate, attached to shells or other submarine 

 substances, they throw out their ramifications in a thousand beautiful 

 plant-like forms. Incrusting the rocks at the bottom of the ocean with 

 calcareous earth separated from the water which bathes them, they 

 silently build up reefs and shoals, justly dreaded by the navigator and 

 sometimes giving origin, as they rise to the surface of the sea, to islands 

 which the lapse of ages clothes with luxuriant verdure and peoples 

 with appropriate inhabitants. 



(113.) Among the calcareous structures derived from the tropical 

 seas, usually known by the 

 general terms Madrepores, 

 Corals, &c., and which, from 

 the beauty of their structure, 

 form the ornaments of our 

 cabinets, few are more com- 

 mon than those denominated 

 Fungice and Meandrince ani- 

 mals belonging to the group 

 Madrephyllicea of systematic 

 zoologists. 



(114.) These masses con- 

 sist of thin plates or laminaa 

 of calcareous matter (fig. 23), 

 variously disposed in different 

 species, but in the Fungia 



agariciformis, which we have Fungia agariciformia 



selected as an example, ra- 

 diating from a common centre, and forming a circular mass resembling 

 a mushroom. When living in its native element, every part of the 



Fig. 23. 



