﻿74 MADEEPORARIA. 



54. Montipora Brueggemanni. (PI. XXXII, fig. 19.) 



Description. — Corallum in its complete form unknown, explanate, 1 to 1 • 5 mm. thick at 

 the growing edge, 2 ■ 5 mm. tliick 4 cm. away. A wiinkled epitheca follows close behind 

 the growing edge. 



Calicles minute, from 0"3to^ 0*5 mm., very scattered, to the naked eye very irregular in 

 shape, some as mere shallow scratchings of the surface ccenenchyma. Under the lens, they 

 are star-shaped, being most regular in, the^ thicker pajt of the corallum, with deep fossa. Six 

 prominent septa, very unequal ia thickness- and, size ; the iaterseptal loculi run into the open 

 spaces of the surface network.. 



In section the streanxing layer is distinct, formed of a few thick cylindrical threads. 

 This forms a thick solid layer on the epitheca ; whiJJe towards the upper surface the threads 

 of the reticulum bend sharply up,, resembling short, thick and very irregular trabeculas. This 

 thickening layer rises here and; there into irregulkr niDunds- which, vary from faint ridges to 

 stout conical eminences nearly 3. mm. high. These tend to slope gradually towards the 

 growing edge and then dip down abruptly.. One or more calicles appear in the angle formed 

 at the bases of these mounds, sometimes on their distal faces. The surface cojnenchyma is 

 covered with frosted gj-anules-which ace the tips-of the- thick vertical elements of the thickening 

 ccenenchyma. 



There are two smaJU fragpients of this type- whichi were previously labelled together 

 M. papulosa, Lamarck, by Buiiggemann ; they have,.howeveii, none- of the special features which 

 are attributed to Lamarck's type. 



The description given above is based chififly upon the langer explanate fragment a, 

 which shows a growing edge. Judging from the very small size- of the calicles, and from 

 their distance apart and consequent fewjaess compared with, the mass of the ccenenchyma, the 

 coral is probably a very slow growing one.. The thick solid layer on the epitheca seems to 

 indicate that the fuU growth is a large- horizontal frond.. The smaUer fragment (h) is a portion 

 of a frond at least 7 mm. thick.. The- stock from, which, it was broken was old and dead, and 

 a small new growth, has started from, its surface and curled venicaUy round the thick 

 fractured edge of its predecessor. 



It is clear that we know too little of either fragment to claim this- as more than a pro- 

 visional grouping. At the same- time;, the specimen a is quite large and. normal enough to 

 represent a new type. 



It is worth noting that the section of the smaller fragment (i.e; of its dead and corroded 

 portion) shows the fan-like arrangement of the threads of the thickening layer which indicates 

 the gradual submergence of papillse ; cf. the same phenomenon in ]\f. amhigua. This suggests 

 that the papUlffi of the adult stock of h were symmetrically nipple-shaped ; if so the fragment 

 should come near M. vernwosa. On the other hand, the calicles have greater resemblance to 

 those of M. Brueggcjnanni, in being very minute, inconspicuous, and irregular. 



a. Fiji Islands. F. M. Eaynor, Esq. (Type.) 



■ ^» Jl 1) U J) 



