CORALS FROM MURRAY, COCOS-KEELING, AND FANNING ISLANDS. 151 



As these specimens present such differences among themselves that each might 

 almost be considered to represent a separate species, each will be briefly described: 



Specimen from line II, 150 feet from shore (plate 62, figs. 1, ia). — Corallum branch- 

 ing, base dead, base of living growth incrusting the dead part. Living part up to 62 mm. 

 tall. Branches simple and tapering, basal diameter 7.5 mm., terminal diameter 3.5 mm., 

 length 18 mm.; or of uniform diameter with obtuse ends; or flabellate, greatest width of an 

 individual terminal 14.5 mm. Dividing terminals may be 40 mm. wide. Single branches 

 dividing at the tip up to 30 mm. long. Anastomosis frequent. 



Calices from 0.3 to a little more than 0.5 mm. in diameter; from 0.5 to 1 mm. apart. 

 Coenenchymal surface between calices flat or somewhat elevated, in the latter condition 

 causing the calicular edges to be depressed. Both the glabrous and foveolate conditions 

 occur on the same branch, the former usually low down on the inner sides of the branches. 

 1 he reticulum is a rather open mesh-work on the upper part of the branches, but is second- 

 arily compacted on the older parts of the corallum. In places costae are simulated. Simple, 

 small spines occur on projections from the coenenchymal trabecular, but they do not form 

 tubercles. 



The calicular walls are distinct, rather thick rings. There are 6 distinct, spiniform 

 septa in each calice and one longer or two opposed longer septa mark a plane of symmetry. A 

 few smaller septa of a second cycle usually present, but the cycle is rarely or never complete. 



Specimen from line II, 180 feet from shore (plate 62, fig. 3; also plate 19, fig. 45, of 

 Dr. Mayer's article).— This is a small clump, 9 by 7 cm. in diameter and 6 cm. tall. The 

 branches are greatly interfused. Most of the surface is glabrous, comparatively small 

 areas having the foveolate character. Six septa are not always so conspicuously developed 

 as in the preceding specimen. 



Specimen A from line III, 1,150 feet from shore. — Corallum forms tufts; branches not much 

 fused among themselves; round or flattened; surface usually foveolate. In some calices 

 the second cycle of septa is complete. Minute costal striations are usual on older parts of 

 the corallum. 



Specimen B from line III, 1,150 feet from shore (plate 62, fig. 2). — Corallum forms a 

 rounded cluster, about 8 cm. in diameter and 6 cm. tall. Branches rather slender, about 

 5 mm. in diameter; terminals often compressed, 7 mm. wide. Surface usually glabrous. 

 Six principal septa not always conspicuous. Calices 0.3 to 0.5 mm. in diameter. This 

 represents Montipora fruticosa Bernard. 



It does not seem possible to separate these specimens into different species, 

 but they seem to me to represent probably four or more of those recognized bv 

 Bernard, viz, AI. divaricata, AI. compressa, M. fruticosa, M. ramosa, and perhaps 

 others. The name AI. compressa (Esper) (non Millepora compressa L.) is not avail- 

 able for this species. M. palmata Dana from the Fiji Islands is a different species. 

 The lower edge of the calice is protuberant and there are small coenenchymal 

 tubercles. Bedot's specimens identified as M. palmata do not belong in the same 

 section of the genus, but are Bernard's AI . fruticosa, which I am here combining with 

 At. ramosa Bernard. 



Dr. Wood Jones collected the species at Cocos-Keeling, where it grows in great 

 luxuriance in shallow water in the lagoon, opposite the eastern end of the Pulu Tikus. 



Distribution. — Cocos-Keeling (Wood Jones) ; Murray Island; Amboina (Bedot); 

 Mactan, Philippines (Bernard), as AI. compressa. 



Foveolate Montiporte. 



Montipora turgescens Bernard. 



Plate 62, figures 4, 4a, specimen from Murray Island. 



1897. Montipora turgescens Bernard, Cat. Montipora, p. 53, plate 6, fig. 2; plate 32, fig. 11. 



The following is a description of a specimen of AI. turgescens from Murray Island : 



Corallum incrusting, creeping over its basal support; edges thin, about 3 mm. thick; 

 older part up to 10 mm. thick. Epitheca extends to the edge. 



