Stephenson, Thomas Alan. (1921). On the classification of Actiniaria. Part II. — Consideration of the whole group and its relationships, with special reference to forms nor treated in Part I. The Quarterly Journal of Microscopical Science, London. New Series, 65(4, 260): 493-576, 20 text-figures.
Stephenson, Thomas Alan
On the classification of Actiniaria. Part II. ï¿½ Consideration of the whole group and its relationships, with special reference to forms nor treated in Part I.
The Quarterly Journal of Microscopical Science, London
It has been necessary, on account of the length of the present paper, to confine Part II to discussions; the definitions of families and genera involved, on the lines of those already given in Part I, will be printed in another issue of this Journal as Part III, which will also contain a list of literature and an index to genera covering Parts II and III. The list of literature will be additional to that printed in Part I, and any numbers given in brackets in the following pages will refer to the two lists as one whole.
Part I dealt with a relatively limited and compact group of anemones in a fairly detailed way; the residue of forms is much larger, and there will not be space available in Part II for as much detail. I have not set apart a section of the paper as a criticism of the classification I wish to modify, as it has economized space to let objections emerge here and there in connexion with the individual changes suggested. Part I tried to clear the ground and discuss the method of attack, so that the arguments there given need not be repeated, and so that the general principle and method suggested there might be taken for granted in Part II. I should like to record here that in these papers on Classification there will be found points in contradiction to certain remarks in earlier papers—'Terra Nova' and 'Actiniaria collected off Ireland'—but the point of view is bound to become modified in some particulars as further experience opens new vistas. That the view-point should remain immovably fixed in the light of developing knowledge would more need apology than that it should march with necessity. Work on Part II has served only to strengthen and confirm the plan suggested in Part I of this paper.
Definitions to be given in Part III are based as far as possible on anatomically-described species, leaving the more doubtful forms to fit themselves in as knowledge of them increases. Consequently lists of species given include rather the betterknown forms on which the definition is founded, than exhaustive enumerations. Even to identify an anemone from an old figure or description is very risky; to be sure of an old species one must obtain and re-describe the type-specimens if such exist. If there are none, it is guess-work—cf. Pax (75), p. 309, and others.