REPORT ON THE HEXACTINLE 13 



added Actinia priapus of Tilesius. The description which 

 Tilesius gives of this Kamtchatkian form, though given at some 

 length and accompanied with numerous figures, leaves one in 

 considerable doubt as to its actual affinites. The figures of 

 the entire animal given in his PI. XIV, certainly resemble very 

 greatly large specimens of M. diantJms, especially those con- 

 tained in the present collection, and I should have little hesita- 

 tion in identifying with that species were it not for Fig. i, of PL 

 XV, which suggests a Thalassianthan character for the ten- 

 tacles. Andres has accepted this figure as representing the 

 true structure of the tentacles and has assigned the form to a 

 new genus Dendractinia, placing it however among the Actiniae 

 incertae scdis. It seems to me quite probable however that the 

 structure of the disc shown in PL XV, Fig. i, is not natural 

 but has been made by dissection, the figure being of a dissected 

 specimen. In the text (p. 407) Tilesius says that the disk *'in 

 quinque vel sex ramos, ramulos et surculos papilliferos villi- 

 ferosve divisus et subdivisus est, ita, ut peripheria disci a numer- 

 osissimis tentaculorum fasciculis formetur." This might be 

 taken as confirming the accuracy of Fig. i, but earlier in the 

 paper (p. 396) be divides Actiniae into two groups, of which the 

 first contains " actinias disco diviso, scilicet in ramos ramulos 

 et surculos tentacula efformantes " and includes Actinia phtinosa, 

 Miiller, Priapus polypus Forskal, Actinia cffocta Baster and 

 Actinia priapus. The same description then which he applies 

 to the tentacles of A. priapus serves also for A. plurnosa, and 

 this, taken in connection with the figures in PL XIV, seems to 

 me to render exceedingly probable the identity of Actinia 

 priapus with Metridium dianthus. It may also be mentioned 

 that from what we now know of the distribution oi M. dianthus 

 there is reaaon to expect its occurrence on Kamtchatkian shores^ 

 while, on the hand, the occurrence of a Thalassianthid is not to 

 be expected, since, so far as at present known, such forms are 

 essentially tropical in their distribution. 



Finally I may add, that if the identification of A. priapus 

 be correct, it is possible that ^vdiWdt's A. farcinien ('35) may also 

 be a synonym. 



