MADREPORA. iter 
long; aperture circular. Star very prominent in all the corallites; the six primary septa 
are subequal, and nearly meet in the middle line in the immersed corallites; in the pro- 
minent ones the outer directive septum is rather broader than the others. 
A small number of immersed or subimmersed corallites have a greater diameter than 
usual, and are provided with a third cycle of septa; but, as in the case of M. mirabilis, the 
calicles with three cycles of septa do not appear to have any constant position. The 
corallum is porous and reticulate in section ; the surface is densely clothed with equal plate- 
like echinulations ; wall more or less distinctly striate. 
a. China (probably South). Fisheries Exhibition. 84. 2. 26. 10. a 
b. Korea Straits. J. F. R. Aylen, Esq., R.N. [P.]. 62. 7.16. 33. | 2 
c. Tsu-sima, Korea Straits. J. F. R. Aylen, Esq., R.N. [P.]. 62. 7. 16. 109.] & 
3. Subgenus POLYSTACHYS. 
Corallum cespitose, bushy or corymbose. Axial corallites cylindrical, little variable, 
usually 2 to 2°5 mm. diameter, usually with a well-developed star of 12 septa. Branchlets 
on the upper surface spiciform, with relatively large ascending corallites, in which rarely 
more than the inner one-third of the wall is undeveloped. This subgenus is connected with 
Lepidocyathus through M. frondosa and M. sinensis. 
A. Corallum cespitose, bushy or subcorymbose, but always convex on the upper surface. 
Corallites nariform to tubo-labellate or tubular ; wall not dense. 
a. Branches rarely under 1 cm. in thickness ; corallite-wall not fragile. 
59. Madrepora nasuta. 
Madrepora nasuta, Dana, Zoophytes, p. 453, pl. xxxiy. fig. 2; M.-Edwards & Haime, Coralliaires, t. iii. 
p. 153; Verrill, Bull. Mus. Comp. Zool. 1864, vol. i. p. 42; ? Moseley, Proc. Roy. Soc. Lond. 
1876, vol. xxiv. p. 549; Quelch, ‘ Challenger’ Reef Corals, p. 154; Rathbun, Proc. U.S. Nat. 
Mus. 1887, vol. x. p. 16 (non B.-Smith, Ann. Mag. N. H. 1890, vol. vi. p. 453). 
Corallum broad cespitose, from a stout solid base, 15 em. diameter in a specimen 
30 cm. across; below complanate and nearly naked, stout pedicellate ; above branchlets 
crowded, digitiform, nearly simple, rarely proliferous, subterete, 5 to 6°25 em. long and 
8 to 10 mm. thick, subacute, branchlets of the margin horizontal and elongate. Radial 
corallites very prominent, compressed-nariform, very finely striate; aperture oblong. Star 
often distinct, the directive septa a little the broadest. (Dana.) 
In the specimen figured the marginal branches do not appear either elongate or hori- 
zontal, and the branches are less simple than one would suppose from the above description. 
One of the ‘ Challenger’ specimens referred by Quelch to this species agrees well with 
Dana’s figure, but not so exactly with the description. Corallum 30 em. broad, 13 em. 
