192 PAPERS FROM THE DEPARTMENT OF MARINE BIOLOGY. 



trabecule.' The pali are weakly developed, or even absent; sometimes 4, those before 

 the lateral pairs, are present; occasionally there is one before the solitary directive, and 

 very rarely is there a suggestion of a pains on the members of the triplet. 



Columella tubercle is a lamella lying in the plane of the directive septa and joined to 

 them; also joined by radii to the lateral pairs and to the laterals of the triplet. There may 

 be considerable compacting of the tangle. 



Habitat, etc, Cocos-Keeling Islands. — Dr. Wood Jones states: "Very abundant 

 and an important constituent of all composite rocks and of breccias. Color the 

 same as in [P. somaliensis]." 



Bernard has made comparative notes on tliose of the Red Sea forms of Porites, 

 which he designates Red Sea (g)i (the species here described), (9)2, and (g)8. The 

 types of four of the massive species described by Dana from the Fiji Islands are 

 in the U. S. National Museum; P. conglomeraia ( = P. lutea M. Edw.), P. fragosa, 

 P. favosa, and P. livwsa. They are markedly different from P. solida. 



Distribution. — Red Sea; Cocos-Keeling Islands. 



2. Porites lobata Dana. 



Porites lobata forma centralis Vaughan. 



Plate 85, figures 2, 2a, 3, specimen from Fanning Island. 



1907. Puntci lohiUa forma centralis Vaughan, U. S. Nat. Mus. Bui!. 59, p. 201, plate 82, fig. 2; plate 83, 

 figs. 2, 2a; plate 84, figs. 1, la, lb, 2; plate 85, fig. i; plate 96, figs. 1-3. 



Two specimens brought by Mr. Elschner from Fanning Island are in the U. S. 

 National Museum. I subdivided forma centralis mto five subformse and designated 

 them alpha, beta, gavinia, delta, and epsilon. One of the P annmg Island specimens 

 (see plate 85, figs. 2, 2a) is subforma beta, in which "the livmg layer is bent under 

 and creeps over a portion of the base." The other specmien is subforma gamma; 

 its calices are represented by plate 85, figure 3. 



As it seems to me that Dana's Porites favosa is surely a synonym of P. lobata, 

 I am introducing figures of it (plate 85, figs, i, la) and a few notes on the type: 



Porites favosa Dana (type No. 672, U. S. Nat. Mus., plate 85, figs, i, la): Calices 

 from 1.25; to 1.5 mm. in diameter, except in depressions, where they may be only I mm. 

 across. The wall forms a distinct elevated ridge. The pali are small, but the formula is 

 normally complete. The figures show the essential details and they may be compared with 

 those contained in my paper on the Hawaiian corals cited in the synonymy. 



Distribution of Porites lobata. — Hawaiian Islands; Fanning Islands; Fiji Islands. 



3. Porites murrayensis, new species. 



Plate 84, figures 4, 40, 4^, u, specimens from Murray Island. Also plate 13, figures 12, 14, of Dr. Mayer's article. 



The following is a description of this species: 



Corallum massive, form hemispherical or subspherical,with attachment on a part of 

 the periphery; surface uniformly rounded or with variously shaped undulations. 



Calices deep, axial fossa a pit; diameter, usually i to 1.5 mm.; in depressed areas 

 somewhat less. 



Wall rather thick, elevated, fairly continuous, interrupted in places, usually straight, 

 occasionally shows zigzagging. Denticles along its upper edges not uniform; on some 

 parts of the surface there are about twice as many as the septa, where they may be com- 

 pressed in radial planes; in other areas they may be tangentially compressed. The denticles 

 are beset with divergent granulations. 



Septa 12 in number, rather thick, interseptal loculi of the same width or somewhat 

 wider or narrower than the thickness of the septa. Septal faces beset with granulations 



'See Bernard's description Porites tolida (Forskal) Klunzinger, Cat. Porites Indo-Pacific, p. 237. 



