34 MADEEPOEAEIA. 



prominent corallites a variable number of immersed ones occur, some about 1 mm. diameter, 

 but the majority much smaller, often under 0*5 mm. The prominent corallites become 

 shorter and more distant on the under surface, where many are subimmersed, but the small- 

 sized immersed corallites appear wanting. Corallum very dense and stony, surface granulato- 

 echiuulate ; wall striate above, the costse becoming divided into dentate plates below. The 

 prominent corallites usually possess 12 septa, all of which are narrow, sometimes only the 

 directives are prominent ; the smaller immersed corallites have only 6 septa. 



The species is at once recognized by the extremely massive corallum without proper 

 branches, but the form of the corallites is similar to that of some varieties of M. muricata. 



West Indies, ? Indian Ocean. 



a. Bahamas. Colonial Exhibition. 86. 10. 13. 10. 



b. ? ? 93. 4. 7. 80. 



9. Kadrepora conigera. 



Madrepora conigera, Dana, Zoophytes, p. 440, pi. xxxii. fig. 2 ; M.-Edwards & Haime, Coralliaires, t. iii. 

 p. 159 ; Studer, Mitth. naturf. Ges. Bern, 1880, p. 22 ; Eathbun, Proc. U.S. Nat. Mus. 1887, 

 vol. X. p. 14 ; Ortmann, Zool. JB. 1889, Bd. iv. p. 503. 



Corallum consisting of massive horizontal (?) plates 2'5 to 6 cm. thick, lobed at the 

 margin, and sometimes deeply subdigitate ; above covered with short and stout subacute 

 cones ; surface plain below. The cones on the upper surface are irregular in size and height, 

 and the narrow intervals between are occupied chiefly by immersed corallites. The cones 

 are 1*2 to 3 cm. in diameter, and 1 to 3 cm. high : some are rather flat above, without any 

 marked axial corallite ; others are more distinctly pointed, with tubular axial corallites 

 2 to 3 mm. in diameter and 2 to 3 mm. exsert ; wall dense, not very thick, and strongly 

 costulate. Radial corallites erect, labellate or tubular, with a more or less oblique aperture, 

 variable in length (2 to 4 mm.), and 1*5 to 2 mm. diameter. A few immersed and short 

 nariform corallites are scattered amongst the others. The lower part of each cone is 

 occupied by elongate oblique tubular corallites, some of which bear 1 to 3 labellate 

 bud-corallites. Primary septa all very narrow, with the outer directive sometimes most 

 marked. Corallites on the flat under surface all very short or immersed, the longest are 

 tubo-nariform. Ccenenchyma very dense, and the surface reticulate with rounded knobs in 

 place of the usual pointed echinulations ; corallite-wall firm and dense, striato-echinulate. 



Singapore. 



a. ? ? 93.4.7.70. 



?*. ? ? 93.4.7.71. 



10. Madrepora smithi. (PI. XXVI. fig. B.) 



Madrepora pyramidalit, Bassett-Smith {mn Klunzinger), Ann. Mag. N. H. 1890, vol. vi. p. 453 (part.). 

 Madrepora seriata, Bassett-Smith (mn Ehrenberg), loc. cit. p. 453. 

 Madrepora paxilligera, Bassett-Smith (mom Dana), loc. cit. p. 453. 



