CLASSIFICATION OF ACTINIARIA 271 



powerful, but ranging from weak diffuse to more definite diffuse and 

 slightly or distinctly circumscribed, weak or moderate in development ; 

 the state may vary even within one species, but the circumscribed form 

 is the more usual and may attain a good strength. (Some of the weaker 

 Bunoda -tis-sphincters are illustrated in Part II, Text-figs. 11 d, f, 

 and 12, d, e.) Tentacles simple, their longitudinal muscles ectodermal. 

 Retractors often strong, diffuse to circumscribed diffuse or even circum- 

 scribed. Gonads may appear on the older mesenteries, or all mesen- 

 teries may be perfect and fertile, save sometimes the directives. Brood- 

 pouches may occur. Siphonoglyphes and directives variable in number. 

 Symmetry hexameral, octanieral, &c., or irregular. 



Species : 



The genotype is B. gemmacea, Ellis and Solander, 1786, p. 3. 



(See Gosse, 1860, p. 190 ; G. Y. and A. F. Dixon, 1889, p. 321.) 

 The other British species are B. thallia, Gosse, 1854, p. 283 



(see Gosse, 1860, p. 195 ; G. Y. and A. F. Dixon, 1889, p. 310). 



B. ballii. Cocks, 1849 (see Gosse, 1860, p. 198), and B. 



alf ordi, Gosse, 1865, p. 41. 

 Foreign species numerous. 



This is a genus somewhat parallel to Sagartia among the 

 Mesomyaria. Its synonymy has been much discussed. The 

 genus Cribrina, like Urticina, seems too vague to be 

 adopted. Against one's wishes it seems necessary to let the 

 familiar Bunodes lapse, since the name was pre-occupied 

 for a Eurypterid in 1854; and Verrill's name Bunodactis 

 steps into the breach with several synonyms. There may be 

 some forms which have been wrongly placed under the genus, 

 and their position should be reconsidered if they do not come 

 under the above definition, which is wide enough already. 

 The genera Bunodactis, Anthopleura, and Aulac- 

 tinia have already been fused by Torrey (1906, pp. 47-52), 

 and I fully agree with him that there is no valid way of separat- 

 ing them. I now add Actinioides to the list of synonyms. 

 It has always represented the Bunodes species with the 

 weaker sphincters, but apparently because of its being placed 

 in the Actiniidae while Bunodes was placed in the Buno- 

 didae, the similarity was overlooked. It is now evident that 

 the Bunodidae and Actiniidae are one and the same family 

 (see Part II, p. 526), and the two genera can no longer be 



