104 



Calicle almost circular set round with four cycles of septa. 

 Septa entire, all about ' 5 mm. exsert, ending perpendicularly 

 against the axial fossa. Primaries and secondaries rather 

 thicker and broader, inner edges slightly thickened and 

 twisted. 



Pali two series, those in front of the primary septa blunt 

 rods, intermediate in size between the rods of the columella 

 and those of the second series in front of the secondary 

 septa, which are so greatly broadened that they extend al- 

 most to "the tertiaries on either side. 



Columella forming a fifth to a quarter of the diameter 

 of the calicle, situated about '75 mm. below the ends of the 

 pali, which again lie i '5 to 2 mm. below the upper edge of 

 the theca, essential, consisting of fine rods (fasciculate type), 

 varying with growth up to about 30 in number. 



Diameter of calicle, 6-9 mm. ; height of corallite, 10-20 



mm. 



Locality. — Lat. 33° 3' S., long. 27° 57' E., 32 fms. ; sand, 

 shell, and rock. 



The septa and pali do not vary from the above description 

 in the three type specimens, but the fourth is constricted round 

 the mouth of the calicle and in its pali, septa, columella, and 

 epitheca closely approaches Alcock's specimen. The columella 

 has five rods only, is equally deeply situated, as in the other 

 specimens, but its rods are not so sharply marked off from the 

 pali. 



Genus HETEROCYATHUS, Ed. and H- 



The genus is characterised by a low, broad, simple corallum, 

 having an As-pidosi-phon living in its base. The coral larva 

 fixes itself on a small Gastropod shell, in the cavity of which the 

 worm takes up its abode. The shell is generally of such a size 

 that the coral in its growth is able to completely surround it, 

 but the Aspidosiphon growing at the same time stimulates the 

 coral to broaden its base, in which it retains a spiral cavity open- 

 ing to the exterior, in which it lives. Where the coral does not 

 so affix itself, its shape is conical, base pointed. Only a single 

 species of the genus appears to be known. A number of so- 

 called species have been described on single or few specimens. 

 All are represented in the series from the Cape or in the col- 

 lection of the British Museum, and it is obvious that they re- 

 present merely the descriptions of isolated specimens drawn by 

 the dredge, etc., at random out of series of the same species. 



