The Actiniae of tlie Plate Collection. 267 



tlie disc were moderately developed and entirely confined to the 

 ectoderm. 



Tliere vvere tweiity-four pairs of perfect mesenteries and twenty- 

 fonr imperfect ones, and in some individuals an incomplete fifth 

 cycle, composed of very small mesenteries, also occurred. In one 

 specimen, No. 158, the mesenteries were arrang-ed octameronsly, there 

 being sixteen perfect and sixteen imperfeot pairs. I examined only 

 one individual from this locality, bnt to judge froni the nnmber of 

 the longitudinal pink lines which adorned tlie column, the others 

 were hexamerous. The longitudinal muscles were rather weak, the 

 pennon being narrow and usually low (Fig. 52), although in the 

 octamerous specimen it was fairly high. There were merely indications 

 of the parieto-basilar and basilar muscles. Acontia were present 

 bnt they were not especially abundant; there were no reprodnctive 

 Organs in the individuals examined. Inner stomata were present 

 but no marginal ones were observed. 



The identiflcation of this form rests largely upon Dr. Plate's 

 Statement, but there seems to be no good reason for doubting its 

 correctness. In Lesson's figure of A. chihnsis the acontia are shown 

 protruding only from the upper part of the column, but in the 

 present forms the cinclidal openings are scattered, though in some 

 cases they are slightly more numerous in the upper than in the 

 lower portions of the column. In general appearance and in coloration 

 the similarities are marked, although it is evident that in the 

 coloration there may be considerable Variation. 



Several species of Sagartians have been described from the 

 Chilian region by Dana (1846), Gay (1854) and Carlgeen (1899) 

 and it is possible that the present species may be identical with 

 some of these. The coloration in some of its varieties suggests 

 Actinia prinrnJa Drayton, but the Statements as to the existence of 

 marginal tubercles (acrorhagi '?) in that form are so precise as to 

 render its Identification with chilensis doubtful without further In- 

 formation as to the exact nature of the tubercles. There do not 

 seem to be sufficient reasons for regarding any of the new species 

 described by Gay and Carlgren as identical with chilensis, although 

 it must be remembered that the distinction of the various species 

 of SagurfUnae is at present very uncertain. 



