﻿46 MADREPOEARIA. 



Calicles minute but distinct, • 5 mm. diameter, opening on the young branches as mere 

 irregular breaks in the reticulum, but lower down through tliick ccenenchymatous rings which 

 are not protul^eraut and often asymmetrical. Six thin and feebly developed septa with faint 

 incomplete traces of a second cycle. Septa are pointed, directives often exsert plates. 



Ccenenchyma consists of a stout open reticulum ; the axial layer is only distinguished 

 from the cortical layer by the disposition of its elements and not by any difference of density. 

 The stout reticulum makes the surface rough. 



The type specimen of this coral is a fragment in the Paris Museum ; its most striking 

 feature is the peculiar circumscribing of the calicles by a stout ring of ccenenchyma. The 

 specimen in our National Collection which comes nearest to it is a somewhat larger fragment 

 which differs from it, as far as I can see, only in the fact that the reticulum is somewhat 

 lighter. The rings round the calicles, the dichotomous branching, and the general size are 

 alike. I had already named this specimen M. f orbed, but after comparing it with the original 

 of 31. rubra, I believe the two are specifically identical. 



From the original description we learn that the twelve tentacles of the polyps are well 

 developed for tliis genus, being swollen and fusiform, but with rounded tips. The whole stock 

 is a bright red-brown colour. 



Our specimen shows a slight difference in the surface texture on the two sides (cf. the 

 specimens of M. Gaimardi) : tlie one side shows the rough reticulum, the other is composed of 

 smooth, thick, serpentine threads (PI. XXXII. fig. 9). 



a. Keeling Island. H. 0. Forbes, Esq. [84. 2. 16. 2.] 



29. Montipora superficialis. 

 Montipora superficialis, Briiggemann (manuscript name). 



Description. — CoraUum ramose, stem cylindrical, 8 mm. thick, young branches short, 

 round and thick. 



Calicles small, ■ 75 mm., conspicuous, crowded but evenly distributed, rather less than 

 one diameter apart. Margin of aperture not defined at surface, hence they appear to the 

 naked eye very irregular in shape. The six primaries distinct and exsert, but not projecting 

 above the highest level of the interstices ; the directives are slightly larger. These exsert 

 septa are mostly smooth, white, conspicuous laminte in striking contrast to the irregular 

 echinulfe of the surface reticulum. The primaries reach to about the half radius circle. 



Ccenenchyma. The axial streaming layer is a coarse, rather close reticulum which 

 changes gradually into the radial cortical layer which is also a coarse, rather solid reticulum. 

 On the more pointed branchlets the axial strand forms the growing tip without calicles ; on 

 the more rounded tips, young calicles appear, but these have not the characteristic septal 

 apparatus ; this only appears on the older calicles opening in the cortical layer. 



The single specimen was named M. superficialis by Briiggemann in his MS. catalogue, 

 and referred to under this name on p. 208 of vol. v. of the Jour. Mus. Godef., 1879. It 

 appears, however, never to have been described by him. The specimen was labelled with the 



