MADEEPOEA. 49 



surface, and the fusions are almost confined to the lower part of the colony. Ultimate 

 divisions often 4'5 cm. long and only 5 mm. thick, gradually tapering, but a few of the 

 branchlets near the base are thicker and more distinctly acuminate. Tubular and proliferous 

 corallites very spreading, 0*4 to 1"8 cm. long, 2 mm. diameter at the apex and 3 mm. at the 

 base, or more in the case of elongate ones which bear a number of very short open nariform 

 buds. The smaller corallites between the tubular ones vary in shape as in var. scandens. 

 The tubular corallites have 6 rather narrow subequal septa ; the star is scarcely developed in 

 the shorter and immersed ones, but sometimes one or both the directive septa may project a 

 little. Corallum moderately porous ; surface striato-echinulate or reticulate and echinulate ; 

 wall finely striate and echinulate or the striae may not be apparent. 



Var. scandens, Klz. 

 The characteristic feature of the form figured by Klunzinger consists in the fact that the 

 majority of the branchlets are short, stout, oblique, and taper suddenly at the apex, but others 

 are more slender and gradually tapering as in the forms already described. The axial 

 corallites are 2 to 3 mm. long and broad, but on the young budding branchlets they may 

 attain a length of 6 mm. The radial corallites are of very variable length and form, 

 appressed and often crowded, so as to obscure the coenenchyma. Some are tubular, 4 to 6 mm. 

 long, with or without buds, and only differ from the axial corallites in the oblique aperture ; 

 between these many are short, dimidiate, or with the outer part of the wall pointed or 

 almost absent; lower down many are verruciform with variously directed aperture, or 

 completely immersed. Corallum porous ; surface striato-echinulate, the echinulations often 

 plate-like and not crowded, on a ribbed, rarely reticulate and trabecular ground ; wall finely 

 striate. 



I can confirm the statement of Klunzinger that Ehrenberg's Heteropora pocillifera, the 

 type of which is in Berlin, is not identical with M. ehrenbergi, as Milne-Edwards supposed. 

 Although the name was evidently suggested by this supposed identity, there is no doubt that 

 Milne-Edwards had before him the Paris Museum type at the time, and his description was 

 based on that specimen, and not on Ehrenberg's ; his name therefore has priority. 



Indian Ocean ; Red Sea ; Persian Gulf. 



a. Red Sea. J. A. W. Harper [P.]. 78. 3. 18. 1. 



b. Kpseir, Red Sea. Klunzinger Coll. 86. 10. 5. 8. (Var. scandens.) 



c. Persian Gulf. A. S. G. Jayakar, Esq. [P.] 92. 1. 13. 1. 



29. Madrepora clathrata. (Plates V., VI. figs. A, B.) 

 Madrepora clathrata. Brook, Ann. Mag. N. H. 1891, vol. viii. p. 459. 



Corallum fan-shaped, reticulate, 30 cm. high, breadth across the upper part 33 cm., but 

 becoming rapidly narrower below. A main stem is absent, and the branches in the lower 

 part have a diameter of about 1 cm. ; their subdivisions are at first only slightly spreading, 

 but become more divaricate above. The branchlets are numerous, 2 to 4 cm. long and 5 mm. 



