112 MADREPORARIA. 
tubular, 4 mm. long. Corallum very porous; surface reticulate, finely echinulate; wall 
fragile, striato-reticulate. 
Pacific Ocean: Great-Barrier Reef area. 
a. Port Denison. ‘Saville-Kent Coll. 96.6. 8.274. (Type.) 
107. Madrepora latistella. (Plate IX. fig. B.) 
Madrepora latistella, Brook, Ann, Mag. N. H. 1892, vol. x. p. 459. 
Corallum subhorizontal, without fusions. Branches 9 to 10 mm. diameter. Branchlets 
on the upper surface erect, spiciform, simple or in groups of 2 to 3 from a common base, 
rarely proliferous except near the margin of the colony; length 2°5 to 3 em., diameter 5 mm, 
Axial corallites cylindrical, 2°5 to 3 mm. diameter, 2 mm. exsert. Radial corallites chiefly 
gutter-shaped or labellate, usually ascending ; wall of moderate length, but becoming reduced 
to a crescentic rim near the base of the branchlets ; length 1°5 to 2 mm., diameter 1°3 mm. ; 
on the marginal branches the corallites are stouter, further apart, and many which are tubular 
or subtubular indicate new proliferations, those which are 4 or 5 mm. long already bear 
several small buds. Star well-developed; even in corallites situated near the apex of a 
branchlet the primary septa are very prominent and a second cycle exists in rudiment ; lower 
down the second cycle is also well-developed. Immersed corallites are numerous on the 
upper surface, and extend to the basal parts of the branchlets. On the under surface the 
branchlets extend obliquely, and often bear several elongate tubular corallites 6 mm. or more 
long and 2 mm. diameter. Corallum moderately porous ; surface strongly striato-echinulate ; 
wall strongly striate, echinulate at the base. 
The species bears a close general resemblance to M. patula, but differs in the form of the 
corallites, in the importance of the septa, in the condition of the surface, as well as in 
minor points. 
Pacific Ocean: Great-Barrier Reef area. 
a. Port Denison. Saville-Kent Coll. 92. 6. 8. 275. le 
6. Thursday Island. Saville-Kent Coll. 92. 6. 8. 316. f§ 72°: 
The following species are also provisionally referred to this subgenus. The first 
shows an affinity to the subgenus Conocyathus, the others are apparently related to 
Lepidocyathus :— 
108. Madrepora polystoma. (Plate XIX. fig. A.) 
Madrepora polystoma, Brook, Ann. Mag. N. H. 1891, vol. viii. p. 466. 
Corallum corymbose and complanate below, 35 cm. wide and 12 em. high, closely 
resembling that of M. concinna in habit. Branches complanate’ below, the basal parts fused. 
into a solid plate with immersed corallites; distal parts with hemicotyloid corallites on the 
under surface and a few lateral, tubular or conical ones. Branches on the upper surface 
about 4 cm. long and 1°3 to 1°5 em. thick, angular below, with crowded immersed corallites ; 
_ a 
