CORALS FROM MURRAY, COCOS-KEELING, AND FANNING ISLANDS. I9I 



Wall ridge definite, often zigzag, mural denticles coarse, roughly frosted; caliccs deep, 0.8 to 

 1.5 mm. in diameter; septa wedge-shaped; columella a deep seated, compressed rough 



style 4- P- fragosa Dana. 



Pali, especially those before the lateral pairs of septa, larger than the septal denticles. 



Wall, a ridge or trimurate, in the latter condition mural trabecul«e obvious; mural denticles 



coarsely granulate; calices shallow or excavated ;■ P- "iistralieiisis new species. 



Wall relatively wide, crossed by radial costs; calices excavated 6. P. mayeri new species. 



: Inner ends of members of triplet form a trident. 



Wall straight, mural denticles delicately frosted; caliccs shallow; corallum more or less Inb- 



ulatc 7- P- haddoni new species. 



Wall thin, straight, mural denticles more coarsely granulate than in 7; calices excavated 



except near edge of the corallum; corallum hemispherical 8. P. somaliensis Gravier. 



Wall zigzag, often interrupted, relatively coarse; corallum subsphcrical, surface undulate. 



9. P. lutea M. Edw. 

 Without greatly pronounced horizontal thickening of the skeletal elements, but with considerable 

 development of twisted and curved flake-like septal processes; septa crooked; septal 

 granules and pali as irregular knots. 

 Calices large, up to 2 mm. in diameter; triplet with trident formation; columella more or less 



attached to the directive of the triplet 10. P. limosa Dana. 



With pronounced horizontal thickening of the skeletal elements, producing a flaky appearance. 



Calices excavated, septal margins sloping, corallum with rounded lobes and flat-topped gib- 

 bosities II. P. viridis Gardiner. 



Calicular fossae, pits sunk between wide mural reticula; upper surface of corallum rounded, 



without gibbosities 12. P. densa new species. 



Corallum composed of columniform lobes. 



Calices excavated; palar formula complete (calicular characters closely similar to those of 



P. lobala) 13. /*. pukocnsis Vaughan. 



Corallum a thin attached lamina. 



Asexual reproduction often by fission, some calices form series 14. P. lichen Dana. 



Corallum ramose. 



Walls flaky, interseptal loculi narrow. 



Usually 2 septal granules; calices shallow or superficial. 



Pali and septal granules prominent 15. /". andrensi new species. 



Pali and septal granules not so conspicuous as in 15 16. P cyhndrica Dana. 



Normally i septal granule which is remote from the palus; calices slightly excavated . . 17- P. nigrescens Dana. 



1. Pontes solida (Forskal) Klunzinger. 



Plate 84, figures 3, 3a, specimen from Cocos-Keeling Islands. 



1879. Parties solida Klunzinger, Korall. Roth. Mcer., pt. 2, p. 42, plate 5, fig. 21; plate 6, fig. 14. 



1905. Porites erythrita: prima Bernard, Cat. Porites Indo-Pacific, p. 236, plate 33, fig. 7. 



1908. Porites solida von Marcnzeller, Denksch. k. k. Akad. Wiss. Wien, vol. 80, p. 65. 



1910. Porites Wood Jones, Coral and Atolls, p. 76, text-fig. 14. 



The following is a description of a specimen of Porites solida from Cocos- 

 Keeling Islands: 



Corallum with a widely expanded incrusting base, above which it thickens and forms 

 a mass with a hillock surface. Diameter up to 18 cm.; thickness up to 7 cm. 



Calices polygonal, excavated, relatively deep. Diameter, 1.5 to 1.75 mm. in depres- 

 sions; up to 2.25 mm. on tops of hillocks; nearly 2 mm. is a frequent size. 



Walls tall, straight, perforate, membraniform, in places a slight development of inter- 

 mural reticulum. Mural denticles about twice as numerous as the septa, erect, frosted 

 rods, w'hich may be compressed radially or in plane of wall. 



Septa of medium thickness, about as thick as the width of the interseptal loculi, faces 

 densely granulate. There are the usual number, a solitary directive, 4 lateral pairs, and 

 a triplet, with the inner ends of its members free from one another. The septa begin some 

 distance below the upper edge of the wall. Septal trabeculae form rather obscure septal 

 denticles, which are only slightly distant from the wall; outer synapticular ring close to 

 the wall and incomplete. 



The pali in this species are peculiar. Within the septal denticles already noted there 

 is a thin plate-like lobe or denticle on each of the 12 septa, and these lobes form a 

 more or less definite ring, simulating pali, but on the lateral pairs they stand outside the 

 points of fusion, while in some instances erect, thin, but not very tall pali actually occur at 

 the point of fusion of the laterals. This ring therefore represents an inner ring of septal 



