76 MADEEPOEAEIA. 



The species is founded on a specimen in the collection of the Boston Society of Natural 

 History. Its habitat is not recorded. 



The specimens which I have referred to this species are subcorymbose, with the branches 

 free. Axial corallites 2"5 mm. diameter, scarcely exsert, with 12 not very prominent septa ; 

 the primary cycle subequal. Radial corallites chiefly gutter-shaped and very spreading, 

 with the outer part of the wall thick and porous, the inner very short and thin or absent ; 

 length 2 to 4 mm., diameter 2 to 2'7 mm. ; the apex is broad and curved in most cases, but 

 occasionally acuminate. The prominent corallites gradually become shorter and verruciform 

 towards the base of the branches. A few of the more elongate corallites bear one or two 

 small buds. Small immersed corallites extend between the others quite to the apex of a 

 branch. The second cycle of septa is incomplete. 



Indo-Pacific Ocean : Great-Barrier Reef area, Madagascar. 



a. ? ? 93. 4. 7. 137. 



b. Rocky Island. Saville-Kent Coll. 92. 6. 8. 287. 



c, d. Capricorn Islands. Saville-Kent Coll. 92. 6. 8. 288 & 289. 



e. Madagascar. W. Deans Cowan, Esq. [P.j. 82. 5. 23. 1. (Var.) 



62. Hadrepora effasa. 



Madrepora effusa, Dana, Zoophytes, p. 455; M.-Edwards & Haime, Coralliaires, t, iii. p. 153; 

 Ortmann, Zool. JB. 1889, Bd. iv. p. 506 (non Quelch, ' Challenger ' Eeef Corals, p. 154 ; rwn, 

 B.-8mith, Ann. Mag. N. H. 1890, vol. vi. p. 454). 



Corallum broad, cespitose, convex above ; base forming a nearly solid disk ; clumps 

 13 cm. high and 28 to 35 cm. wide. Branchlets crowded, digitiform, 3'8 cm. long and 8 to 

 10 mm. thick, those at the margin coalescent. Axial corallites stout, cylindrical, rather over 

 2 mm. broad. Radial corallites compressed nariform, much crowded and unequal, 3 mm. 

 long ; but others are quite short, and some are tubo-nariform or tubular and proliferous. 

 Under surface crowdedly covered with short corallites. (Dana.) 



Dana says that the species resembles M. nasuta, but has much more unequal corallites 

 (M.-Edwards states erroneously " plus uniformes "), and the axial corallites are twice as broad. 

 The branchlets are also much shorter, the marginal ones coalescent and the under surface 

 muricate. The type specimen is apparently not preserved in the National Museum at 

 Washington, and unfortunately we know nothing of the diameter and the angle of the 

 corallites or the thickness of the wall &c. The form which I take to be the species named 

 by Dana has rather crowded somewhat ascending corallites, which are very variable in length 

 and form. Many are nariform or tubular, with an oblique or dimidiate aperture ; in each 

 case the outer part of the wall is thickened, but porous ; the longer ones bear buds ; 

 numerous immersed or slender corallites occur between the more prominent ones. Wall 

 striato-echinulate ; surface very strongly echinulate, 



Indo-Pacific Ocean : Ceylon, Great-Barrier area. 



a. ? Mantell Coll. 41. 1. 13. 13. 



b, c. Palm Island. Saville-Kent Coll. 92. 6. 8. 283 & 284. 



d, e. Rocky Island. Saville-Kent Coll. 92. 6. 8. 292 & 293. (Var.) 



?/•. ? ? 93.4.7.117. 



