152 MADEEPOEAEIA. 



8'5 cm. long, with the subdivisions chiefly on the under surface ; nearer the base two or three 

 rows of shorter twigs occur provided with radiating and stout cylindrical corallites with 

 rounded apex (7 to 16 mm. long and 3 to 5 mm. diameter), with or without buds. Axial 

 corallites 5 to 6 mm. diameter, cylindrical, with plane apex when small, but margin strongly 

 cuned in all other cases. Wall thick and fenestrated, aperture small, star well developed. 

 Radial corallites tubular, with a more or less oblique aperture, more rarely nariform, 

 increasing in length and diameter from the apex downwards for a distance of about 3 cm., 

 below which a few are more elongate, but the majority short, becoming nipple-shaped and 

 dilated nearer the base, none are completely immersed on the branches. Diameter of the 

 small periaxial buds 1 mm., of an average corallite 1'8 mm., of the more elongate ones below 

 2'5 mm. ; length 1 mm., 2"5 mm., and 5 mm. respectively ; the majority have the inner part 

 of the wall a little thinner than the outer and the margin is plane ; in the stout elongate 

 corallites the wall is of uniform thickness and the margin more or less rounded. The angle 

 formed by the corallites increases towards the middle of the branches and in a few cases 

 approaches 90°. The star is very well marked in all but the younger corallites and consists 

 of a well-developed primary series of septa and a more or less prominent second cycle. 

 Corallum moderately porous ; surface reticulate ; wall striate and echinulate. 



The type specimen is similar in appearance to certain specimens of M. canaliculata, but 

 differs in the complete absence of dimidiate corallites and in the much better developed star. 



Pacific Ocean : Great-Barrier Reef area. 



a. Port Denison. Saville-Kent Coll. 93. 6. 8. 238. (Type.) 



160. Madrepora globiceps. 



Madrepora ghUeepg, Dana, Zoophytes, p. 454, pi. xxxiv. fig. 3 ; M.-Edwards & Haime, Coralliaires, t. iii. 

 p. 153; ?Verrill, BuU. Mus. Comp. Zool. 1864, vol. i. p. 42; Rathbun, Proc. U.S. Nat. Mus. 

 1887, vol. X. p. 16 ; ? Verrill, Proc. Essex Instit. 1866, vol. v. p. 23 ; ibid. 1869, vol. vi. p. 100. 



Corallum broad cespitose, convex above, 30 cm. broad and 15 cm. high, with a solid disc- 

 shaped base. Branchlets erect, digitiform, crowded, subangular, about 6 cm. long and 1-3 to 

 1*7 cm. thick, rounded at the apex. Axial corallites 2 mm. broad, scarcely at all prominent. 

 Radial corallites crowded (the figure shows them rather distant), short tubiform or tubo- 

 nariform, 1'5 mm. broad, obsolescent below. Aperture oblique and elliptical; wall obsoletely 

 striate; star distinct. (Dana.) 



A small corymbose specimen in the collection of the British Museum, growing on 

 a species of Tridacna, agrees fairly well with Dana^s figure of this species, but the apices of 

 the branches are not so obtuse. The branches are 3-5 cm. long and 1 cm. diameter at the 

 base, slightly tapering to a rounded apex; apices about 2 cm. apart. Axial corallites 2-5 to 

 3'5 mm. diameter, scarcely exsert. Radial corallites tubular, unequal, but nearly all are very 

 short, spreading almost at right angles, immersed below ; the more prominent ones are nearly 

 2 mm. diameter, rarely 2 mm. long; wall thickened, margin not rounded; aperture often 



