62 MADKEPORAEIA. 



by Quoy and Gaimard at Tongatabu, the specimen is preserved in the Paris Museum. This 

 is the form understood by Dana as M. pocillifera. 



The Barrier Reef specimens referred doubtfully to var. incrassata are difficult to separate 

 from some specimens of M. millepora in case the lip is short and thick. 



Pacific Ocean : Great-Barrier Reef, New HebrideSj Fiji, Tongatabu, Tahiti. 



a-c. Api, New Hebrides. H.M.S. ' Challenger.' 86. 12. 9. 227, 228 & 413. 



rf, e. Tongatabu. H.M.S. ' Challenger.' 80. 11. 25. 231 (part). 



/. Port Denison. . SaviUe-Kent Coll. 92. 6. 8. 24. 



g. Lady Elliott Island. Saville-Kent Coll. 92. 6. 8. 215. 



A. Baudin Is., N.W.Australia. H.M.S. ' Penguin.' 92. 1. 16. 6 (part). 



86. 12. 9. 231. { = M. laxa, Quelch.) 

 91.9.9.3. ( = M. /aa?a, Quelch.) 

 92. 6. 8. 25 to 27 & 30. 

 92. 6. 8. 28. 

 ? A. Low Woody Island. Saville-Kent Coll. 92.6.8.29. 



43. Madrepora aspera. 



Madrepora aspera, Dana, Zoophytes, p. 468, pi. xxxviii. fig. 1 ; M.-Edwards & Haime, Coralliaires, 

 t. iii. p. 142; Studer, MB. Akad. Wiss. Berlin, 1878, p. 533; Quelch, 'Challenger' Eeef Corals, 

 p. 156; Rathbun, Proc. U.S. Nat. Mus. 1887, vol. x. p. 12. 



? Madrepora prostrata, Quelch (non Dana), ' Challenger ' Reef Corals, p. 163. 



The following is a summary of Dana's description : — 



Corallum arborescent, spreading, ramose; branches terete, 12 mm. thick, summits conical 

 and proliferous. Corallum quite porous, surface scabrous ; axial corallite nearly 3 mm. diameter, 

 a little prominent ; the radial short labellate, fragile, divaricate, not crowded, many obsolete ; 

 cells quite large, the immersed ones below, 1 mm. broad. Star very short-rayed, the directive 

 septa prominent. The species was described from a fragment 75 cm. in length. 



The ' Challenger ' specimens referred by Quelch to this species appear properly identified, 

 but as they diflfer in several points from Dana's definition, a description of them is sub- 

 joined : — 



Corallum arborescent or bushy, about 21 cm. high; main branches 1*4 cm. diameter, 

 much divided, branches scarcely tapering, and maintaining a diameter of over 1 cm. 

 to within 3 or 4 cm. of the apex. Extremities much divided, many of the branchlets 

 bear proliferations near the apex. Axial corallites 2-5 to 3-5 mm. diameter, about 2 mm. 

 exsert ; wall usually thick and porous, strongly costate, but often with large deep funnel- 

 uhaped cup, as in M. pocillifera, but smaller. Radial corallites crowded, especially above, 

 lahellate, spreading at right angles ; lip broad, half-tubular in the larger corallites, narrower 

 and more pointed in the others. Maximum length of corallites which remain radial 2 mm., 

 breadth ol lip 2 mm., but the majority are smaller ; a few immersed corallites are scattered 



