28 CORALS AND CORAL LSLANDS. 



sionally met with in Actinias, the description of which is briefly 

 given on page 20. The bud commences as a sHght prominence 

 on the side of the parent. The prominence enlarges, a mouth 

 opens, a circle of tentacles grows out around it, and increase 

 continues till the young finally equals the parent in size. 

 Since in these species the young does not separate from the 

 parent, this budding produces a compound group ; and the 

 process often condnues until in some instances thousands, or 

 hundreds of thousands, have proceeded from a single germ, 

 and the colony has increased to a large size, sometimes many 

 feet, or even yards, in breadth or height. Such is the species 

 of Dendrophyllia represented in the figure on page 31, and 

 the Madrepora figured on page 29 ; in both of which, and in 

 all such coral zoophytes, each stellate cavity or prominence 

 over the surface corresponds to a separate one of the united 

 polyps. 



The compound mass produced by budding — which consists 

 of the united polyps with the corallum as their united secre- 

 tion — was called in the Author's Report, a Zoophyte, it being 

 truly animal in nature, though under a plant-like form through 

 the plant-like process of budding. But the word to many 

 minds conveys the idea that the species is something between 

 a plant and an animal, which is totally false ; and besides, 

 it is often used distinctively for the division of animals in- 

 cluding the sponges. As a substitute the term Zoofhome may 

 be employed, derived from the Greek L,u)oy, animal, and Ow/jiog, 

 a /ieaj> — a term applicable also to compound groups in other 

 classes, as, for example, those of Rhizopods, Bryozoans and 

 Ascidians. The term zoophyte, where employed beyond, 

 signifies a zoothome formed of united polyps, or a polyp- 

 zoothome. The coral of the zoothome being the corallum, 

 that of each polyp in the compound corallum may be called a 

 corallet — the term calicle, formerly used by the author for the 

 same, being now restricted to the polyp-cell. 



It is obvious that the connection of the polyps in all com- 

 pound groups must be of the most intimate kind. The 

 several polyps have separate mouths and tentacles, and separate 



