58 MADREPORAEIA. 



are obtuse at the apex. 2. There are no apical clusters of short branchlets. 3. Stout 

 proliferous corallites, though not absent, do not form a marked feature. 4. Immersed 

 corallites appear to be entirely or almost entirely absent. 



Tahiti. 



38. Madrepora pharaonis. 



Madrepora pharaonu, M.-Edwards & Haime, Coralliaires, t. ill. p. 143 (non Briiggemann, Phil. Trans. 



1879, vol. clxviii. p. 574). 

 ? Madrepora pustuloga, M.-Edwards & Haime, Coralliaires, t. iii. p. 144 (non Briiggemann, non Klun- 



zinger). 

 ? Hettropora laxa, Haeckel, Arab. Korallen, pi. 2. fig. 7 (won Ehrenberg, non Lamarck, &c.). 

 Madrepora mierocyathus, Klunzinger, Korallenth. d. roth. Meores, p. 22, pi. iii. fig. 3, pi. iv. fig. 19, 



pi. ix. fig. 17. 

 Madrepora scandens, Ridley & Quelch (non Klunzinger), in H. 0. Forbes's Naturalist's Wanderings in 



the Eastern Archipelago, London, 1885, p. 44. 



Type. Corallum arborescent with stout branches, between which occasional fusions occur, 

 recalling the habit of M. crassa. Branches 2"3 cm. thick, 30 cm. long, laxly subdivided. 

 Axial corallites 2'5 mm. diameter, 1*5 mm. exsert; septa in two cycles, the directives scarcely 

 broader than the other primaries. Radial corallites chiefly immersed, with a few labellate, 

 but scattered between are tubular ones almost at right angles, about 5 are distributed to each 

 2'5 cm. ; these are 3 mm. long and 2 mm. diameter, and mostly bear a rosette of short 

 labellate corallites. The tubular proliferous corallites have apparently only 6 septa, the 

 directives much broader than the others. In the immersed corallites the septa are more 

 nearly equal. Corallum moderately porous ; surface reticulate and echinulate ; wall striate 

 and fragile. (The specimen appears worn.) 



Another specimen in the Paris Museum, from the same locality, is labelled M. pustulosa, 

 and if this should prove to be the type of M.-Edwards's species it is certainly not distinct 

 from the above. M.-Edwards, however, gives Seychelles as the habitat of his M. pustulosa ; 

 but 80 far as I can ascertain there is no specimen of the species from that locality in the 

 collection, and the description given agrees fairly well with this specimen. The specimen 

 here referred to is a fine well-preserved form with the following characters : — Main branches 

 3 cm. thick, much divided, with numerous spreading and tapering branchlets. Axial coral- 

 lites 2-5 to 3 mm. diameter, 3 mm. exsert. Radial corallites simple, tubular with oblique 

 aperture, of variable length up to 4 mm., and 1-5 mm. diameter, at an angle varying from 

 60° to 80°, with short, nariform, labellate and immersed ones between. This is the 

 arrangement on the younger branches ; in other parts the tubular corallites become elongate 

 and proliferous, up to 2-5 cm. in length, 5 mm. diameter at the base, with tubo-labellate 

 bud-corallitcs at an angle of about 60°; the majority of the proliferations are, however, only 

 from 5 to 7 mm. long. This specimen appears to me to give the real characters of the 

 species better than the type. 



A third specimen of enormous size, over 1 m. diameter, shows the proliferations still 

 more elongate, forming branchlets averaging 15 mm. in length. All three specimens are 

 from the Red Sea, and were collected by Botta in 1837. 



