l86 PAPERS FROM THE DEPARTMENT OF MARINE BIOLOGY. 



crowded, appressed tubular or tubo-nariform, with occasional immersed corallites between; 

 on the lower surface there are many immersed corallites, and near the base there may be 

 no calicular apertures. 



Ccenenchyma echinulate-costulate; becomes very dense and subvitreous. 



Station. — Off northwest reef, Murray Island; depth 15 fathoms. 



Distribution. — Great Barrier (figured type from Palm Island); Samoa; South 

 Seas (Brook). 



Acropora syringodes groups with Acropora carduus (Dana), with which Brook, 

 also associates A. striata (Vernll). The specimen just described does not com- 

 pletely accord with the description of A. syringodes, but the form of the branchlets 

 and the size and arrangement of the corallites are so similar that it can scarcely 

 belong to another species. The looser branching may be attributed to its growth 

 in deeper water. 



Family PORITIDjE Dana. 

 Genus GONIOPORA Quoy and Gaimard. 

 1833. Coniopora Quoy and Gaimard, Voy. de I' Astrolabe, Zool., vol. 4, p. 218. 



Type species: Goniopora peduncidata Quoy and Gaimard. 1 



Bernard, in his catalog of Goniopora, abandoned any attempt to group speci- 

 mens into species and merely described the morphologic variations of the specimens 

 according to localities. He recognized twelve variations in the Great Barrier Reef, 

 six in northwest Australia, and one variation from Australia without definite 

 locality. Goniopora fruticosa Saville-Kent and Goniopora calycularis (Lamarck) 

 appear to be the only species based on specimens from Australia. Bernard, in his 

 "Supplementary List of Goniopora?," 2 adds three variations to the Great Barrier 

 Reef fauna, one to that of Torres Strait, and one to that of Northwest Australia. 



Goniopora tenuidens (Quelch). 



Plate 84, figures I, 2, specimens from Murray Island. Also plate 14, figure 17, of Dr. Mayer's article. 



18S6. Rhodaraa tenuidens Quelch, Reef Corals, Challenger Reports, p. 188, plate 8, figs. 7, ya, yb. 

 1903. Goniopora Moluccas (1)1 Bernard, Cat. Goniopora, p. 65, plate 4, fig. 7 



As this species is represented by a suite of 14 specimens, the opportunity will 

 be used to describe it in detail. First a healthy specimen of average appearance 

 will be described and the others will be compared with it. 



(1) The form is pulvinate. The initial colony grows from a small base into a sub- 

 spherical corallum attached on one side, with a well-developed basal epitheca. The older 

 part of the corallum dies and successive cushion-like growths form on top. The super- 

 position of cushions may be repeated two or more times, but apparently does not result 

 in the production of tall columns composed of what appear to be successive caps as does one 

 of the Oligocene fossil species from Anguilla, British West Indies. Total height of specimen, 

 102.5 mm.; greater diameter, 95 mm.; lesser diameter, 65 mm. (including dead corallum), 

 51 mm. (living part). One other specimen is larger, but none exceeds the size of a man's 

 double fists. 



The usual diameter of a fully developed calice is 3 mm.; very young ones may be less 

 than 1 mm. in diameter, while there are a few monsters, one is 5 mm. in diameter. Depth 

 up to 2.5 mm., probably a little more. Although the usual method of asexual reproduction 

 is by gemmation in the angles between the calices, equal fission occasionally takes place. 



The walls are usually simple and narrow; in places show some zigzagging; perforate 

 between the stepta, which have thickened upper and outer ends; occasionally there is 

 some reticulum where the calices are not so crowded. 



'See Bernard's notes on this species, Cat. Goniopora, p. 36, 1903. 

 'Brit. Mus. (Nat. Hist.), Cat. Madreporaria, vol. 6, pp. 145-164, 1906. 



