76 CORALS 



the coralluin and the polyps it is more nearly related to the 

 Imperforata. 



In all the genera there are more than twelve septa, as 

 in most of the Imperforata, and a special character of the 

 fnmilv is that some of the septa fuse along their inner margins 

 to form a number of triangular interseptal spaces. In 

 most of the genera the septa and thecal walls are armed 

 with spines or small tubercles, but only in rare cases do they 

 join to form synapticula. The family includes both simple 

 and colonial forms. 



Balanophyllia. — The little coral called by Gosse ^ " the 

 scarlet and gold star coral " [Balanophyllia regia) is a 

 representative of the solitary Eupsammiidae that is found 

 in British seas. It was found by that author attached to 

 the rock-pools at low-tide near Ilfracombe, associated with 

 the Devonshire cup coral [Caryophyllia smithii, Fig. 2, p. 

 26). It has since been found in other localities off the coasts 

 of Devonshire and Cornwall, but it is still far from being 

 one of the common objects of the seashore. 



The dried corallum (6-8 mm. in height and diameter) 

 can readily be distinguished from that of Caryophyllia by 

 the two Eupsammiid characters — the perforation of the 

 walls and septa and the confluence of some of the septa 

 to form triangular interseptal spaces with their bases on 

 the thecal wall. The polyp is like a little sea-anemone 

 with a mouth situated on a cone rising from the centre of 

 the oral disc, and the margin of the disc is provided with 

 a single cvcle of about fifty long tentacles. Gosse described 

 the tentacles as " conical, obtusely pointed, without terminal 

 knobs," and there is little doubt that this is a good descrip- 

 tion of what he saw in the rock-pools at low tide. But de 

 Lacaze-Duthiers, who studied this species, from the coast 

 of France, alive in a small aquarium, says that when fully 

 expanded the tentacles are long and finger-like, and temiinate 

 in little knobs as in Caryoph3dlia. As in the latter coral 

 also, the sides of the tentacles are armed with batteries of 

 nematocysts which have the appearance of little warts. 



The colours of the Devonshire specimens were described 



' P. H. Gosse, British Sea Anemones and Corals, iS6o, p. 343. 



