ORDERACTINOIDEA. 59 



structure in the two cases. The germinating power required is, 

 therefore, similar, and might be expected to belong to the same 

 reproductive organs. It hence appears, that while the margins of 

 the ovarian lamellae develope ovules, the inner portions often develope 

 buds. Milne Edwards farther states, that the side of a visceral 

 cavity which gives out buds, does not produce ovules within. The 

 formation and growth of the bud absorbs, for the time, the general 

 reproductive powers of that part of the parent-polyp. 



The disk-buds, like the lateral, probably proceed from one of the 

 same lamellae, and they differ from the latter principally in the posi- 

 tion of the budding-point, which is immediately below the disk, 

 instead of from an inferior lateral origin. 



2. INFLUENCE OF THE POSITION AND CHARACTER OF THE BUDS, AND 

 MODE OF GROWTH, ON THE RESULTING FORMS OF ZOOPHYTES. In the 

 exposition of this interesting subject, it is important in the first place 

 that some idea be given of the various forms which zoophytes assume. 

 We shall next consider how far modes of growth influence these forms, 

 and then to what extent they depend upon the additional function of 

 gemmation, and proceed from the positions, character, or periodicity 

 of buds. 



A. FORMS OF ACTINOID ZOOPHYTES. 



55. Many of the various shapes which these zoophytes assume, 

 are familiarly known. Madrepore shrubs and trees, and the sea-fan 

 and other Gorgonioe, from the West and East Indies, are common 

 in collections. The hemispheres of brain-coral (Meandrina), and 

 also of star-coral (Astrssa), are often met with. It is very generally 

 supposed, that these are by far the most frequent, if not the only 

 shapes presented ; but, on the contrary, the varieties are extremely 

 numerous, as we have already intimated. Some species grow up in 

 the form of large leaves rolled around one another like an open cab- 

 bage, and cabbage-coral would be no inapt designation for such 

 species. Another foliated kind consists of leaves more crisped and 

 of more delicate texture, irregularly clustered; lettuce-coral would 

 be a significant name. Each leaf has a surface covered with polyp- 

 flowers, and was formed by the growth and secretion of these polyps. 

 Clustered leaves of the acanthus and oak, are at once called to mind 

 by other species ; a sprouting asparagus-bed by others. The mush- 

 room is here imitated in very many of its fantastic shapes, and other 

 fungi, with mosses and lichens, add to the variety. 



The vases of flowers, to which allusion is made on a preceding 



