358 FUNAFUTI ATOLL. 



inner walls are short and the immersed corallites are more 

 numerous. 



Radial corallites of the branchlets and of the central region 

 are labellate or tubo-labellate ; they are longer and narrower 

 than those on the under surface. They average about 1 mm. in 

 diameter and vary from 2 to 3 mm. in height. 



The axial corallites are from 2 to 2 -5 mm. in diameter and are 

 2 mm. exert. The septa of the axial corallites are twelve, the 

 primaries are well developed, and the directives meet below. In 

 the radials of the upper surface there are usually only six septa ; 

 the directives are a little broader than the rest. On the lower 

 surface of the branches, pedicel, and base, the septa are in two 

 cycles, the primaries broad, the secondaries narrow, and the direc- 

 tives meet at the base. 



Echinulse flat; denticulate plates O'l mm. apart. 



On the upper surface of the corallum the ridges on the walls of 

 the corallites are 0'2 mm. apart; on the lower they are about - 15 

 mm. Each ridge, when unabraded, has two longitudinal rows of 

 spinules, which arise from the crest on either side ; they are 

 opposite or alternate, and diverge at such angle as to project over 

 the interstices between the ridges. 



Reefs in the lagoon. 



MADBEPORA FBUTICOSA, Brook. 

 Madrepora fruticosa, Brook, Cat. Madr. Corals, Brit. Mus., i., p. 



138, pi. xviii., fig. A. 

 One small specimen obtained on the reefs in the lagoon. 



MADREPORA EURYSTOMA, Klunzinger. 



Madrepora eurystoma, Klunzinger, Die Korall. Rothen. Meeres, 

 ii., p. 16, pi. i., fig. 8, pi. iv., fig. 7, a, b, pi. ix., fig. 12. 



One specimen obtained in the lagoon. 



The corallum is subcorymbose, and is attached by an incrusting 

 base to a dead specimen of the same species. The living portion 

 is 10 cm. high, and 14 cm. in diameter The stouter main branches 

 are angular, often compressed and fused at the base, varying from 

 1 to 2 cm. in thickness ; towards their summit they give off 

 numerous short simple branchlets, usually about 2 -5 cm. in length, 

 4 to 5 mm. in diameter, and 1 to 2 cm. apart at the apex. They 

 are fairly uniform in diameter, except the apical third which 

 tapers to the base of the axial corallite. 



The basal corallites are immersed or subimmersed ; the septa 

 are in two cycles, both narrow at the summit ; the primaries 

 become broader below and often meet in the centre. 



The radial corallites on the basal portions of the branches and 

 branchlets are immersed, or short and verruciform towards the 



