The Actiniae of the Plate CoUection. 253 



the brown of tlie column being mingled with a g-reenisli tinge and 

 a very distiiict line surrounding the margin as in tlie majority of 

 the paler specimens. 



The tentacles were usually colorless, although in sonie of the 

 broAvn specimens they partook of that color. A noticeable marking 

 in many of the specimens was a dark band around the margin of 

 the mouth opening, and in some cases there was also a similar band 

 surrounding the base of the elevated peristome. These two bands 

 are shown in Dana's figure of A. achates, and they occur in 

 individuals of the present collection which in otlier respects resemble 

 A. reticulafa. 



Strncture. I have little to add to the descriptions already 

 published. I may State, however, that I have not found in any of 

 the specimens I have examined as many mesenteries as Heetwig 

 has described; my finds agree with those of Carlgren who describes 

 only six complete cycles, though indications of what seems to be an 

 incomplete seventh cycle occur. The specimen described by Hertwig 

 was a little longer than any ofthose described by Carlgren and myself, 

 and this may account for the diiference, although possibly Hertwig 

 may have made a mistake in the order of the interseptal space 

 which he examined for the determination of the arrangement of the 

 mesenteries. I find but three cycles of perfect mesenteries. while 

 Carlgren describes four, the fourth, however. reaching the stoma- 

 todaeum only in its uppermost part. 



I find the mesenteries of the fourth, fiftli and sixtli cycles to 

 be perfect, but although I have examined a number of specimens I 

 have not yet observed any cases of hermaphroditism such as both 

 Hertwig and Carlgren have described. The number of Actinians 

 known to present hermaphroditism is constantly increasing and the 

 question is suggested whether all species do not really exhibit 

 protandric or protogynic hermaphroditism, or whether at different 

 seasons or under different circumstances of nutrition the same indi- 

 vidual may not at one time produce male reproductive cells and at 

 another ova, the two kinds of cells being sometimes present simultan- 

 eously. This idea was long ago suggested by my observations on 

 Cerianthus americamis, in which I found no indications of herm- 

 aphroditism, although the species had been described as hermaphrodite 

 by Louis Agassiz and Mr. Alex. Agassiz informed me by letter 

 that there could be no doubt but that this was the condition in 

 the specimens described by bis father. 



