266 T. A. STEPHENSON 



Genera : Actinia, Anemonia, Gyrostoma, Condy- 

 iactis, Parantheopsis, Bunodactis, Tealia, 

 Epiactis, Isotealia, Pseudophellia, Bolocera, 

 Leipsiceras, Boloceropsis, Dofleinia, Ixa- 

 .1 a c t i s , G 1 y p h o s t y 1 u m , and perhaps others ; see 

 below. 



Actinia, Browno. 



Dip] act is, McM., 1889, p. 110. 



Hormathia as used l)y Hertwig for A. deli ca tula 



(1888, p. 15). 



Actiniidae with smooth body having a collar-like margin, with a fosse 

 between itself and the tentacles, in which lie acrorhagi. The latter are 

 simple or more or less compound, usually conspicuous (e.g. blue) in 

 colour, and can be covered up by the margin in contraction. Tentacles 

 simple and typically retractile, their longitudinal musculature mostly 

 or wholly ectodermal. Sphincter absent to weak or strong diffuse, 

 sometimes with a mesogloeal tendency, but endodermal actually. 

 Mesenteries may be all fertile save directives. Retractors diffuse, 

 may be strong. (.Sphincter of A. equina. Part TI, Text-fig. 11, B.) 

 Species : 



A. equina, L., 1766-8, p. 1088. ( = A. mesembryanthemum, 



EllisandSolander. 1786, p. 4=A. cari, D. Ch., 182.5, p. 233. 



See Gosse, 1860, p. 175 ; Pax, 1907, p. 53 ; Clubb, 1898 ; Andres, 



1883, pp. 397 and 402 ; and Simon, 1892.) 



A. delicatula, Hertw., 1888, p. 15. (See Haddon, 1898, p. 459; 



Carlgr., 1900, pp. 31-3.) 

 A. bermudensis, McM., 1889, p. 111. 



A. tenebrosa, Farquhar, 1898, p. 535; Stuckey, 1909. p. 380. 

 A. kraemeri. Pax, 1914, p. 413. 



I have listed under Actinia those species which seem to 

 definitely belong to the genus as here defined. Sometimes 

 rather vague forms are allotted to it, and there seems to be 

 a certain amount of confusion with regard to it, and to the 

 allied genera. It is actually quite a distinct genus, and there 

 seems to be no reason for mixing it up ^\-ith Anemonia 

 or Gyrostoma. A. equina is of course the commonest 

 of our British anemones, and A. tenebrosa seems to be 

 its southern representative. Verrill (' Trans. Connect. Acad.', 



