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 Turbinaria as well as in Montipora the young 
buds appear in the undifferentiated coenenchyma 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- 
pora and its daughters. Principal or directive septa occur 
and can be accounted for in the same way as in Madrepora. 
Astreopora.—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¢). Asa 
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 
echinule. One apparently natural consequence of this was 
a considerable degeneration of the septal apparatus in the 
daughters of the colony. 
Montiporine.—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. 4d). 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 coenenchyma, which is 
nothing but the result of fusion of the greatly thickened 
porous walls of the individuals of the colony. ‘The budding 
