FISSION IN ACTINIA BERMUDENSIS VERRILL 45 



are sufficiently transparent to show the attachments of the 

 mesenteries. The inner edges of the complete mesenteries (be- 

 low the level of the stomenteron) as well as those of the incom- 

 plete mesenteries are provided with mesenteric filaments. These 

 at their bases give rise to long, much convoluted acontia. 

 These organs are protruded through the mouth, and not through 

 cinclides. Gonads are present on all of the mesenteries of the 

 first and second orders, except the two pairs of directives; and 

 a few traces of immature gonads were also found on some of the 

 mesenteries of the third order. Only one ostium, the median, is 

 generally present in the mesenteries of Actinia bermudensis. 



The tentacles, arranged in two very irregular rows, are from 

 eighty-five to one hundred and twenty in number in mature 

 specimens, and at the bases of the outer row are twenty-four 

 irregularly spaced, bright bluish-violet eminences, the acrorhagi. 



This species of sea anemone was first described by VerriJl in 

 1898, and since that time has been observed and worked upon 

 by several investigators. No mention, however, has been made 

 of specimens of a double nature, and, except for a single speci- 

 men kept in the laboratory for some time as a curiosity by Dr. 

 Crozier, I believe the specimens obtained during the summer of 

 1916 are the first individuals having either double heads or 

 double mouths that have been carefully examined. The speci- 

 men Dr. Crozier found had a double mouth and more than the 

 ordinary number of tentacles, but it underwent no visible changes 

 while under observation. 



While working on the early embryology of Actinia bermuden- 

 sis, I had occasion to examine carefully over a thousand speci- 

 mens of all ages, and all but a very few were of the bright red 

 variety. Among this number of animals were two which first 

 attracted attention by their size and shape. The oral discs were 

 greatly elongated, the long axis being almost twice the length 

 of the shorter, which had normal dimensions. On examination 

 it was found that one specimen (fig. 1) had two separate diglyphic 

 mouths, the long axes of which made a slight angle with each 

 other. In the other specimen (fig. 2) the mouth was in the proc- 

 ess of division. The mouth opening had roughly the shape of 



