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Discosoma anemone Duchassaing, 1850. 

 Stoichactis anemone Haddon, 1898. 

 ? Actinia helianthus Ellis, 1767. 

 . ?Hydra helianthus Oken, 1816. 



Discosoma helianthus Duch. and Mich., 1860. 

 Stoichactis helianthus Duerden, 1900. 



There was no Duchassaing label with the single specimen of this 

 species, but the De Filippi label read Discosoma anemone Duch. 



An examination of the arrangement of the tentacles and of the 

 sphincter shows that this form is beyond doubt identical with that 

 which I described as Discosoma anemone (1889) and also with that 

 described by Duerden (1900) as Stoichactis helianthus. 



The synonomy of the species is somewhat complicated and its history 

 may be briefly stated in justifìcation of the name given it above. Ih 

 1767 Ellis described and fìgured two forms from the West Indies which 

 he named Actinia anemone and A. helianthus, but the descriptions 

 are too imperfect to be available for a distinction of the two, and in 

 the figures the principal difference that can be observed is that A. 

 helianthus, is somewhat smaller than A. anemone. Subsequent authors 

 simply included Ellis' terms and figures in their works, and in 1850 

 Duchassaing referred A, anemone to the genus Discosoma. Later in 

 1860 Duchassaing and Michelotti described and fìgured D. anemone 

 from living specimens and in 1864 the same authors stated their beliel 

 that A. anemone and A. helianthus were the same species, a view in 

 which I concurred in 1889. 



In 1898 Duerden described two species of Discosoma from Jamaica, 

 one of which was evidently indentical whith that which I had described 

 as D. anemone, while the other lacked verrucae and had a diffuse 

 sphincter (Duerden, 1900), its tentacles being also arranged on quite 

 a different pian. This latter form Duerden identified with Ellis' ane- 

 mone, naming it Homostichanthus anemone, while my anemone he 

 identified with Ellis' A. helianthus, without, however, presenting any 

 very good reasons for the change. Carlgren (1900) from an examination 

 of the Turin specimen was convinced that it was identical with my 

 anemone, and thought that this was Ellis' helianthus on account of 

 the sinuous margin which is indicated in the figure of that form. But, 

 for the avoidance of confusion, he suggested that helianthus and ane- 

 mone be regarded as a single species, which, following Duerden, he 

 named Stoichactis helianthus, and gave a new name, H. Duerdeni, to 

 Duerden's IL anemone. In this arrangement Duerden (1902) aquiesced. 



We have, then, the two originai species of Ellis, which cannot now 

 Ite distinguished, uor is there any likelihood that they ever will be ; 

 and we have the D. anemone of Duchassaing eertainly identical with 



