﻿PAPILLATE MONTIPOR^. 71 



52. Montipora spumosa. (PI. VIII. % 1 ; PL XL ; PL XXXII. fig. 16.) 



Pontes spumosa, Lamarck, Anim. sans Vert., 2nd edition, ii. (1816) p. 273. 

 Montipora spumosa, de Blainville, Manuel (1834) p. 389. 

 Pontes venosa, Ehrenberg, Korallenthiere (1834) p. 118 (see Klunzinger). 

 Non Manopoi-a spumosa, Dana, Zoophytes (1848) p. 495, pi. xliv. fig. 1. 



Description. — Corallum encrusting, massive or running up into tall branching lobes 

 covered with small calicle-bearing knobs. ' An epitheca is everywhere developed under the 

 creeping edges. 



Calicles immersed below level of coenenchyma, closely and evenly distributed over the 

 whole corallum, even on the tips of the knobs, about a diameter apart, under 1 mm., star-like 

 when seen directly from above. Two cycles of septa ; primaries short and tliick ; the 

 secondaries are like notches in the square interseptal loculi ; fossa deep. 



Coenenchyma in section purely reticular, although, in the encrusting forms, the 

 thickening layer may sometimes become almost trabecular. This reticulum rises everywhere 

 between the calicles as a rather coarse flaky network, the flakes standing up, twisted and with 

 jagged edges. These interstitial upgrowths are quite irregular : at one point, they spring up 

 carrying the surface up into humped knobs, or even lobed branches ; while, between such 

 excrescences, small areas of the ccenenchyma are often perfectly smooth. 



There can, I think, be little doubt that under this, name Lamarck was describing and 

 naming the coral figured by Knorr in his ' Delicite Naturae Selectse.' * The coral which 

 that figure is meant to represent seems not to have been recognised again, for while de 

 Blainville merely adopts it as a Montipora {sjnimosa), Dana gave Lamarck's name to a very 

 different coral (see M. hispida) and Milne-Edwards suppressed it, making it synonymous with 

 Montipora monasteriata of Forskal. The figures given in Knorr's plates are, as a rule, suffi- 

 ciently true to life, and lead us to believe that any particular figure represents the essential 

 features of the object delineated. Fortunately, there is a specimen in the National Collection 

 resembling in all essentials Knorr's figure, which thus justifies- us in re-establishing Lamarck's 

 sjmmosa (see PL VIII. fig. 1). 



The essential feature in this type appears to be the irregular rising up (foaming) of the 

 interstitial coenenchyma to form knobs and lobes which- may grow into branches. The 

 corallum commences as a creeping encrusting growth, which may develop more or less evenly 

 in thickness, the surface being humpy and knobbed, or merely greatly roughened by the 

 irregular upgrowths of the ccenenchyma. From such forms, branched lobate masses can easily 

 be deduced. The branches form thick gnarled or knobbed cylinders, or else clumps of thinner 

 irregular upgrowths, or again the whole corallum may tower upwards in solid castellated 

 masses, not separating into branches at all. (PI. XI). 



There are in the collection eighteen specimens which I have found it expedient to 

 arrange under this heading, in spite of the variations which they show. They all agree in this 

 irregular foaming of a reticular interstitial ccenenchyma. 



* Nurnberg, 1772, pi. A^, fig. 4. 



