1893.] A. Alcock — Newly-recorded Corals from the Indian Seas. 145 



Tlie quinaries unite with the quaternaries much nearer to the 

 columella than to the calicular margin, and close to the columella the 

 quaternaries unite with the tertiaries. 



All the septa are thick, spongy and perforate at their exsert tips 

 and near the wall of the calice, but they soon become thin and dense 

 with surfaces so finely granular as to appear quite smooth to the 

 naked eye. 



The columella is broad, spongy, and strongly convex. 



The colour of the corallum is white, of the soft parts bright scarlet. 



The greatest height of the corallum is 27 - 5 mm., the major dia- 

 meter of the calice 25 mm., and the minor diameter 17'5 mm. 



Dredged by the " Investigator," off Ceylon, in 32 fathoms. 



Heteropsammia, Edw. & Haime. 



15. Heteropsammia geminata, Verrill. 



Heteropsammia geminata, Verrill, American Journal of Science and 

 Arts, second series, vol. xlix. 1870, p. 370. fig. 1. 



About two hundred and fifty specimens were dredged by Professor 

 Wood-Mason in the Andaman Sea. All have the base perforated and 

 tunnelled. 



16. Heteropsammia rotundata, Semper. 



Heteropsammia rotundata, Semper, Zeitschr. Wiss. Zool., vol. xxii. 

 1870, p. 265, taf. xx, fig. 10. 



I refer to this species several specimens from the Persian Gulf 

 presented by Mr. W. T. Blandford, F.R.S. 



17. Heteropsammia aphrodes, n. sp. PL V, figs. 9, 9a. Near Heterop- 

 sammia ovalis, Semper. 



Corallum with a single calice, the wall formed of a fine lace-like 

 reticulum (not spongy as in other species). 



Calice oval and deep, its major diameter being not much less than 

 that of the base — the basal "spur" excluded. 



Septa in four beautifully regular and complete cycles. Those of 

 the first two cycles are of equally predominant size, are exsert, and are 

 very thick, inflated, spongy, and porose, even up to their edges. Those 

 of the fourth cycle are rather larger than those of the third, and unite 

 in front of them, with beautiful symmetry, near the columella. 



The deeply seated columella is well developed, and is slightly 

 concave. 



The greatest height of an average corallum is 10 mm., with a calice 

 having a major diameter of 10 mm., and a minor diameter of 8 mm. 



Numerous living specimens were dredged by the "Investigator" 

 off the Ganjam Coast, at a depth of 20-25 fathoms, and every oue of 

 them was provided with a commensal Sipunculoid worm. 



