356 



COELENTERATA — ANTHOZOA 





large, cylindrical, and spiny. Villogorgia, D. and M. ; widely 

 distributed. Delicate, graceful forms, with thin coenenchyni. 

 Echinomuricea, Verrill ; Muricea, Lamouroux ; Paramuricea, 

 Koll ; Acam2')togorgia, W. and S. ; Behryce, Philippi. 



Fam. 5. Plexauridae, — In this family we find some of the 

 largest and most substantial Gorgonids. The axis is usually 

 black, but its horny substance may be impregnated with lime, 

 particularly at the base. The coenenchyni is thick, and the 

 zooids are usually completely retractile, and the surface smooth. 



The species of the 

 family are princi- 

 pally found in 

 shallow water in 

 warm or tropical 

 regions. 



The principal 

 genera are: — Eu- 

 nicea, Lamouroux. 

 The calices are pro- 

 minent, and not 

 retractile. Plcxaura, 

 Lamouroux; Euplex- 

 aura, Verrill. Eiini- 

 cella, Verrill. With 

 an outer layer of 

 peculiar torch- 

 shaped spicules. The only British species of this order is 

 Eunicella cavolini (formerly called Gorgonia verrucosa). It is 

 found in depths of 10 to 20 fathoms off the coast of the 

 English Channel and west of Scotland. Occasionally specimens 

 are found in which a gall-like malformation with a circular 

 aperture is seen, containing a Barnacle. Such gall formations, 

 common enough in some species of Madreporaria, are rarely 

 found in Alcyonaria. 



Fam. 6. Gorgoniidae. — This family contains some of the 

 commonest and best-known genera of the order. Tliey usually 

 form large flexible branched colonies with delicate horny axes 

 and thin coenenchyni. The ^ooids are usually completely 

 retractile. 



The principal genera are : — Gorgonia, Linn. This genus 



Fio. 156. — Eunicella cavolini. Some branches of 

 dried specimen, showing a gall formed by a Cirripedc 



lars 



