The Actiniae of the Plate CoUection. 263 



specimen aud 96 in the smaller ones. In the latter a section taken 

 inimediately belo^' the nmrgin showed fortj^-eight pairs of perfect 

 mesenteries with intervening imperfect ones, biit lower down onl}' 

 twenty-four pairs were still connected with the stomatodaeum, and 

 still lower only twelve. In other words there were five cycles of 

 mesenteries of which the first fonr were perfect; the first three 

 cycles were sterile and the fonrtli and fifth fertile. I did not 

 examine a specimen with six cycles to determine how many were 

 perfect, but fonnd in one individnal that the fourth, fifth and sixth 

 cycles were fertile. Both external and internal stomata were present, 

 the former being small. 



The longitudinal muscles at the level of the stomatodaeum form 

 a low band, composed of short and for the most part simple folds 

 (Fig. 42 a). They are situated nearer the inner than the outer part 

 of the mesentery and occupy only a comparatively small part of its 

 surface. Inimediately external to the muscles the mesenteries were 

 very thin, but fui'ther out they became thicker and bore a distinct 

 parieto-basilar muscle (Fig. 42 b), whose edge formed a fold and in 

 some cases a series of cavities formed by the irregulär fusion of the 

 muscle with the surface of the mesentery could be distinguished. 

 The basilar muscles were well developed, having the form shown in 

 Fig. 43; those on the endocoelic faces of the mesenteries were con- 

 siderably stronger than those on the exocoelic faces. 



There seems to be no reason for doubting that tliis species is 

 identical with that described by Dkayton as Actinia clematis and, 

 furthermore it is almost as certain that Deayton's A. ßorida must 

 be regarded as a synonym. Carlgren (1899), from a study of 

 numerous specimens contained in the Natural History Museum at 

 Hamburg and the Reichs-Museum at Stockholm, has come to the 

 same conclusion. It seems to me exceedingiy probable that the 

 synonymy should be extended still further and include the form 

 described by Drayton (1846) as Aciinia phivia. This species was 

 obtained at Callao, Peru, and in its general form resembles P. 

 clematis very closely. In the description given by Dana, however 

 it is distinctly stated that the "upper margin [is] not tuberculate", 

 and on this account the species was referred by Milne Edwards 

 (1857) to his genus Cereus and by Gosse (1860), Verrill (1869) 

 and Andres (1883) to the genus Bunodes. The locality from which 

 the species was obtained is identical with that from which the 

 original specimens of P. fiorida were collected, and the difi'erence in 



Zool. Jahrb., Supplement. Bd. VL (Fauna Chilensis. Bd. IIL) Heft i. IB 



