132 Mr. H. M. Bernard on the 



The parent polyp dies away, and its primitive protuberant 

 cone is immersed under the ccenenchyma formed from the 

 fusion of the walls of -a ring of daughters. These daughters 

 carry on the colony, the budding of the daughters being 

 limited to their free or outer sides, ^*. e. to the sides turned 

 away from the axis of the cup. Hence the fact referred to 

 above, that in Turbinari'a as well as in Montipora the young 

 buds appear in the undifferentiated ccenenchyma which forms 

 the growing edge of the cup. This edge represents morpho- 

 logically the outer sides of the combined porous walls of the 

 last-formed ring of polyps, and differs from the porous wall 

 of the parent polyp mainly in the facts, (1) that the laminate 

 radial structures are more or less obscured, and (2) that the 

 epitheca has been left behind. The polyps forming the 

 Turbinarian colony develop equally, and there is no such 

 disparity in size as is seen between the axial polyp of Madre- 

 poi-a and its daughters. Principal or directive septa occur 

 and can be accounted for in the same way as in Madrepora. 



Astrceopora. — The budding is promiscuous ; a new bud 

 develops wherever there is room for it, each one typically 

 carrying up its wall into a protuberant cone (fig. 4 c). As a 

 result of this crowding the known forms are, without exception, 

 thick encrusting, or massive. The costal radial structures of 

 the original parent ceased to be laminate, but broke up into 

 radial series of spines, the tips of which formed protective 

 echinulge. One apparently natural consequence of this was 

 a considerable degeneration of the septal apparatus in the 

 daughters of the colony. 



Montiporince. — The original parent polyp was distinguished 

 by great thickness of its porous walls, which apparently 

 early arrested the development of the polyp, and by a 

 tendency of the whole skeleton to be low, and even perhaps 

 disk- like, and not to rise up into a cone as in the last 

 three genera (fig. 4 c?). In the modern Montipores this has 

 reached its extreme limit, but in Anacropora the habit of 

 forming conical walls is not yet lost. The synapticular con- 

 nexions between the radial structures reached far in towards 

 the centre, so that the visible septal apparatus tended to 

 be limited to rows of septal spines ; when the calicles protrude 

 {Anacropora), and hence grow a little in size, laminate septa 

 appear. The tendency to enormous thickness of porous 

 wall was inherited by the daughter polyps. Hence the two 

 chief characteristics of the genus — (1) minuteness of the 

 polyp-cavities, (2) great richness of ccenenchyma, which is 

 nothing but the result of fusion of the greatly thickened 

 porous walls of the individuals of the colony. The budding 



