﻿GLABRO-FOVEOLATE MONTIPOR^, 49 



Group II.— GLABRO-FOVEOLATE. 



33. Montipora ramosa. (PI. V. figs. 1, 2, 3 ; PI. XXXII. fig. 3.) 



Description. — Corallum a tuft of cylindrical but irregularly bent and swollen stems, 

 either all short, thick, massive, and nodulated, or tall, slender, and tapering. The tips of the 

 branches often expand and give off irregular clusters of short tapering lobes, which rise into 

 branchlets, either more or less fused together or diverging. The size of the cluster depends 

 upon the thickness of the branch. The lower portions of the stems die down, the living coral 

 being about 12 cm. deep. 



Calicles small, conspicuous, crowded, about 1 diameter apart, 0*75 mm., with very 

 irregular margins. Primaries symmetrical, reaching to about the half radius circle, thin, 

 composed of such straight series of spines as to suggest their being laminate ; two directives 

 conspicuous, often laminate. N"o developed secondaries. 



Ccenenchyma very densely reticulate, the axial streaming layer early obscured by the 

 thickening of its elements. It appears, however, less dense at the tips of the more finely 

 tapering processes, which are often without any calicles. Thicker and more rounded excrescences 

 with greater diameter than the axial strand are always covered with calicles. The peripheral 

 reticulum of the thicker stems is also very dense, its radial elements being thickened lil-ce 

 irregularly nodulated trabeculee. In the higher portions, on the tapering points and rounded 

 knobs, the reticulum rises up in the interstices to form the typical foveolate ridges. The 

 ridges are rounded swellings of a rather close granular reticulum. In the lower and older 

 portions of the stems these flatten out, and the surface is almost smooth, the reticulum becom- 

 ing more dense, and the calicular apertures smaller and hence further apart. The granules on 

 the surface are the ends of the reticular threads (see PL XXXII. fig. 3). 



There are five specimens of this coral, representing two complete stocks, and three 

 fragments of a third. The methods of growth of the three are at first sight very different. 



The largest specimen (a, PI. Y. fig. 1) has a thick nodulated stem. The clusters of thin 

 processes from the tips of the branches fuse together. Divergence of these thin processes 

 might at any time give rise to a thin-stemmed stock in the next period of growth. On the 

 other hand, it is more probable that the method of growth, once started, perhaps by some 

 accident, is persisted in throughout. For instance, there is on the dead portion of this specimen 

 a small, thick, cushion-shaped mass about 1 • 5 cm. in diameter, resting on an epitheca. This 

 looks like a young colony, and having a broad base to rest on appears as if it might grow up 

 into a massive stock. On the other hand, a young colony on specimen e, which is a corroded 

 portion of a thin-stemmed stock, having only a narrow base, viz. one of the thin stems, to 

 rest on, begins at once to throw up a thin stock. 



It seems very probable, then, that the character of the stock depends largely upon the 

 accidental conditions in which each young colony starts growiag. 



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