Madrepora in the British Museum. 461 



M. conferta^ Quel., and M. hyacinthus^ Dana ; total thickness 

 2"5 centim. Under surface flattened, openly reticulate, 

 without projecting branchlets ; corallites very short, open 

 bursiform or immersed; diameter nearly 2 millim,, wall 

 rarely 1'5 millim. long. Branchlets on the upper surface 

 arranged usually in groups of two to five along the course of 

 each branch, 9 to 14 millim. long and 4 millim thick. 

 Apical corallites cylindrical, 1'5 millim. diameter. Lateral 

 corallites short, spreading, round labellate, with curved lip ; 

 length 1*5, rarely 2 millim., diameter 1"2 to 1*5 millim. Star 

 not recognizable. 



Thursday Island {Saville-Kent). 



Madrepora Rayneri. 



Corallum horizontal, forming fronds similar to those of 

 ill/, speciosa, Quel., but less confluent and dense. Branches 

 scarcely flattened, naked below, except for a few scattered 

 and appressed twigs, 1 centim. or more long. The upper 

 surface of the branches bear scattered, appressed, nariform 

 corallites and a few which are immersed. Branchlets erect, 

 varying in importance from elongate simple corallites to stout 

 divided twigs, each bearing several elongate radiating coral- 

 lites at the apex. Elongate tubular corallites 1 to 1*6 centim. 

 or more in length, 2*5 millim. diameter at the base, and 2 

 millim. at the apex, margin suddenly contracted. Star well 

 developed. 



Fiji {F. M. Rayner). 



Madrepora recumhens. 



Corallum subcespitose at first, becoming flattened, frondose, 

 or semivasiform with increase in size. Proximal portions of 

 main divisions fused into a solid plate in the larger specimens, 

 without branchlets below. Branchlets on the upper surface 

 short, subconical, and somewhat arcuate, 1 to 2*5 centim. long, 

 and 8 to 13 millim. diameter, rapidly tapering, usually simple. 

 Apical corallites 2 millim., rarely 2-5 millim,, in diameter, 

 cylindrical. Lateral corallites nariform to tubo-nariform or 

 tubo-labellate, with smaller and immersed ones between ; 

 prominent corallites often in rows ; length 1 to 2 millim., 

 diameter I'O to 2 millim.; wall firm, but not thick. Star 

 indistinct. 



Great Barrier Reef {Saville-Kent). 



Madrepora reticulata. 

 Corallum complanate or reticulate ; branches elongate, but 



