40 MADREPORARIA. 



rising in the cylindrical calicular pits, in these lateral calicles it is conspicuous both on 

 account of this rosette and of the mural ring of 24 teeth (septa). 



In section of the base the coral is very solid, the reticulum being coarse and apparently 

 composed both of very thin and very thick threads ; tabulte can be seen round the edges of 

 the base, towards which the calicles radiate. 



This coral has the same general type of calicle as Mr. Quelch's ' Challenger ' type, called 

 by him G. tmuidens (see G. Molhuxas 1, p. 65). They resemble one another (1) in having the 

 same circular calicles as if punctured into the surface; (2) in having a similar coarse re- 

 ticulum along the top edges of the walls ; and (3) in their prominent lamellate pali. 



The same general type of structure is also seen in G. Celebes 1 and G. North- West 

 Australia 1, etc., see Table III. But in all cases their differences are very great, and their 

 scattered distribution hardly allows us to group them under one heading. 



a. Zool. Dept. 84 11. 21. 27. 



6. Goniopora Solomon Islands (4) 3. (PL I. fig. 3 ; and PI. XL fig. 3.) 

 [Shortland Island, Solomon Islands, col. Dr. Guppy ; British Museum.] 



Description. — Corallum forms smooth oval masses with flattened top and with very slight 

 attachment. The edges creep a short way under. A stout epitheca appears under them. 



Calicles polygonal, large (4-5 mm.), open and shallow, except at edges which are 

 growing over dead surfaces on the top of the stock. The walls hardly rise above the 

 columella ; they are very uniform in height (1 mm.) and in thickness (1 mm.), and are built 

 up of a coarse, rather close reticulum, with an irregular median ridge. The 24 septa project 

 as rows of two or three short knobs down the walls, often a little swollen at the tips. All 

 three cycles eventually reach the columella. The interseptal loculi are open and conspicuous, 

 and the columella is a large convex mass of coarse reticulum, its horizontal flakes giving it an 

 appearance of solidity. The jagged irregular paliform granules show their origin from the 

 points where the septa meet by being often V-shaped. Their grouping, however, is very 

 irregular, and the [typical formula difficult to make out. In the denser, more shallow calicles 

 at the sides, these paliform knobs fuse together into solid triangular scales, and are then 

 visibly the fused ends of groups of septa, 3-4 to each scale ; or else the large, solid, almost 

 flat columella shows ridges corresponding not only with the primaries, but with the 

 secondaries, and even some of the tertiaries. 



The single specimen of this coral, which is remarkable on account of the great size and 

 uniform shallowness of its calicles, is interesting in its apparent method of growth. Its form 

 is irregularly globular, and looks as if a fresh layer of coral were spreading over the whole 

 mass from one end, and that this layer, even though incomplete, had itself already begun to 

 die down in its older parts. This at first sight suggests that the whole coral was built up by 

 alternate waves of fresh growth, oscillating from end to end. And this view receives some 



