398 COELENTERATA ANTHOZOA chap. 



Fam. 1. Turbinoliidae.^ — The corals included in this family- 

 are mostly solitary forms attached to foreign objects, or living 

 partly embedded in sand. In some cases a small colony is 

 formed by gemmation. 



The genus Flabellum is a solitary coral of a compressed top 

 shape. It has a large number of septa arranged radially on the 

 cup-wall. This cup-wall is not a true theca but an epitheca. 

 In some forms root-like tubes grow out from the sides of the 

 cup near its base and may serve to support the coral on solid 

 objects. In some remarkably fine specimens recently obtained 

 from the Persian Gulf these tubes served to attach the coral to 

 a telegraph cable. Flabellum seems to be cosmopolitan in its 

 distribution. It is usually found in deep or moderately deep 

 water, but some specimens have been dredged in water of 2 to 9 

 fathoms. 



Garyophyllia is a conical coral fixed by a slightly expanded 

 base. The cup-wall is a true theca covered below by an epitheca. 

 There is a spongy columella surrounded by a single circle of 



pali. There is one British species, 



(''^^'llA^^^I ^" ^™'''^''''^'*- It is found attached 



-^Mllili^ffilw *° shells at a depth of about thirty 



JWtoWI^^vc^ ^^t'^^^^s ^^^^ ^^^ Eddystone Light- 



^"^Ssssil-jfc^^j^sa^^aB^^ house and in other localities in 



^j ^«si^ j.-|^g English Channel. It also 



Fig. 174.— Side view of Trochocyathus ocours between tide marks in the 



hastatm, with exsert septa well- g^iny Islands, and is found off the 



, marked costae (c), and with three ■' 



spinou.s projections (Sp) at the base Shctlands, On the West COast of 



formed by outgrowths from primary gcoi^land and the <?niitb wpst nf 

 costae. (AfterG.C. Bourne.) OCO Liana, aUQ tne SOum-WeSt 01 



Ireland. The genus is widely dis- 

 tributed and extends from shallow water to depths of 1500 

 fathoms. Garyophyllia sometimes occurs in clusters which have 

 the appearance of an incipient colony. This may be due to the 

 embryos fixing themselves upon the epitheca of existing indi- 

 viduals and developing there. It is doubtful whether the species 

 ever reproduce asexually either by gemmation or by fission. 

 When the zooid is fully expanded it projects some distance 

 above the corallum and shows a very transparent body-wall 

 with a crown of some fifty tentacles. Each tentacle terminates 

 in a globose head (Fig. 169) charged with nematocysts. The 

 general colour is pale pink, and there is a broad brown circle 



