MADREPORA. 159 
corallites are chiefly ascending, and numerous small ones are scattered between those which are 
most prominent. Star scarcely recognizable or not prominent. Corallum rather dense ; 
surface reticulate and echinulate; wall striato-echinulate, but the striz become lost as the 
wall increases in thickness. 
This species resembles M. australis in the form of the corallites. 
Indo-Pacific Ocean : Rodriguez, Great-Barrier Reef. 
a, 6. Capricorn Islands. Saville-Kent Coll. 92.6.8. 285 & 286. 
c,d. Rodriguez. Royal Society [P.]. 76.5.5.101 & 106. 
(= M. seriata, Brigg.) Types. 
?e. Rodriguez. Royal Society [P.]. 76.5.5. 107. | 
(= M. haimei, Briigg., part.) 
169. Madrepora leptocyathus. (Plate XVI. fig. C.) 
Madrepora leptocyathus, Brook, Ann. Mag. N. H. 1891, vol. viii. p. 463. 
Corallum flattened vasiform, from a broad base, not pedicellate. Marginal branches 
oblique, fused into a solid plate below, excepting near the periphery, where they are a little 
flattened and covered with short, crowded, appressed, tubular corallites with a thin wall. On 
the upper surface all the branchlets rise from a solid base with very numerous immersed 
corallites. The branchlets are about 3 cm. long and 1 to 1:4 em. thick, frequently angular 
below, but more tapering above; the apices are usually 1°7 cm. apart. Those in the centre 
are chiefly simple, but may bear a few proliferous corallites; others, particularly near the 
margin, are divided. Axial corallites 2°5 to 3 mm. diameter, cylindrical, scarcely exsert. 
Radial corallites small, crowded, tubular or tubo-labellate, spreading at right angles, wall thin 
and porous; they are 1°5, rarely 2 mm. diameter, and seldom over 2°5 mm. long, a little 
unequal, with small and delicate ones between. On the lower parts of the branchlets the 
prominent corallites are not so numerous and the wall is thickened. Proliferous corallites 
5 mm. long and 4 mm. wide (including the lateral buds). Star usually indistinct, but the 
directive septa are sometimes prominent. Corallum rather dense; surface finely reticulate 
and echinulate ; wall striato-echinulate. 
The type specimen appears to consist of two circular colonies fused together. 
Samoa. 
a. Samoa. Rev. S. J. Whitmee [P.]. 75. 10.2.7. (Type.) 
170. Madrepora brevicollis. (Plate XX VII. figs. A, B.) 
Madrepora brevicollis, Brook, Ann. Mag. N. H. 1892, vol. x. p. 454. 
Corallum cespito-arborescent, or subcorymbose and oblique ; branches 8 to 12 em. long 
in the bushy form, 1:5 em. thick ; in oblique specimens the branches may be 22 cm. or more 
in length, but do not increase correspondingly in thickness. In bushy specimens the branches 
we 
