CORALS FROM MURRAY, COCOS-KEELING, AND FANNING ISLANDS. 203 



A restudy of a paratype of the species, No. 22236, U. S. Nat. Mus., leads to 

 a modification of the foregoing description. On some septa there are two inter- 

 mediate denticles or granules between the palus and the wall. As the figure of the 

 calices in my Hawaiian monograph lost so much in reproduction that it is not satis- 

 factory, a new figure is here published (plate 90, fig. 2), and is placed alongside the 

 figures of calices of the specimen from Fanning Island. It will be noted that in the 

 calices of the latter, although there are usually two septal denticles outside the palus 

 ring, sometimes there is only one. Here it may again be remarked that it is often 

 difficult to decide whether a tooth on a poritid septum represents a trabecula or is 

 only a trabecular process.' 



The growth-form of the Fanning Island specimen is shown by plate 90, figure i. 

 The corallum consists of ascending, more or less clavate lobes, which are flattened 

 on top. 



Distribution. — Hawaiian Islands; Fanning Island (C. Elschner). 



14. Porites lichen Dana. 



Plate 90, figure 3, specimen from Cocos-Keeling Islands. 



1846. Porites lichen Dana, U. S. Expl. Exped., Zooph., p. 567, plate 56, fig. 3. 



1907. Porites lichen Vaughan, U. S. Nat. Mus. Bull. 59, p. 214, plate 90, figs. 2, 2a, zh. 



The only character in the Cocos-Keehng specimens which seems to need special 

 consideration is the triplet. The usual condition is for the inner ends of the lateral 

 members to reach the palar ring of synapticulae, where occasionally a cross-bar or 

 membrane may join them to the ventral directive and stand above the level of the 

 columella tangle, but there is much irregularity in the septal grouping. The type 

 of P. lichen was re-examined to ascertain the constancy with which the laterals of 

 triplet fuse to the directive. In some instances the laterals do not fuse by their 

 edges to the directive. There is much irregularity and frequently both directives 

 can not be recognized with certainty. In some instances there appears to be no 

 triplet, but a single septum represents it. The irregularity in septal arrangement 

 is probably due to asexual reproduction frequently being by fission. The variation 

 overlaps, so that the forms, in my opinion, represent one species. 



Habitat, etc., Cocos-Keeling Islands. — Dr. F. Wood Jones states in his notes: 



"Not uncommon on the barrier. The color of the coral is very constantly yellow with 

 the exposed part of the zooid brick red. Found only as an incrusting layer." 



Distribution. — Fiji Islands (Dana's type); Cocos-Keeling Islands. 



15. Porites andrewsi, new species. 

 Plate 91, figures i, la, 2, 2a, specimens from Murray Island. Also plate 14, figure 16, of Dr. Mayer's article. 

 1905. Porites queenslandics duodecimo Bernard, Cat. Porites Indo-Pacific, p. Ii5, plate 19, fig. 6. 



The following is a description of this species: 



Corallum forming clumps of irregularly crooked, anastomosing branches, the summits 

 of which are often divided into tufts of divergent branchlets. Height of corallum exceeds 

 115 mm. Diameter of branch low down 12.5 by 20 mm. Length of terminal branchlets up 

 to 22 mm.; branchlets taper toward obtuse tips, 3.5 to 4 mm. in diameter; or have com- 

 pressed, obtuse tips up to 5 by 12 mm. in diameter. Where a branchlet is subdividing the 

 width may be as much as 20 mm. Depth of living tissue ranges up to 45 mm. 



Calices shallow, small, usual diameter between thecal summits about 1.25 mm. Fossa 

 about two-thirds the calicular diameter. 



Mural summits indefinite, mural trabeculoe terminate in irregularly shaped, curly, 

 flaky, frosted denticles which are incompletely fused. 



'For a discussion of the poritid septum see U. S. Nat. Mus. Bull. 59, pp. 169-216, especially pp. 169-170. 



