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PROCEEDINGS OF THE 



[Feb., 1858. 



were less circular in outline than on the day before. However, their 

 centres of radiation, though more eccentric, were more entirely 

 disconnected with each other than yesterday; and the bodies of 

 the two incipient individuals appeared to be connected only near 

 their upper parts. In fact, the process of fission seems to begin 

 below, and gradually to progress upward; it is the bases which 

 are first separated, and the process there begins by the Actinia's 

 stretching out its base in an oblong form, if I am to judge by the 

 condition of some specimens, wherein I think fission is about to 

 begin. In one such instance, I remarked, to-day, that the centre 

 of radiation was much elongated, while the tentacular crown was 

 still undivided. Sometimes, however, in such cases, the tentacula 

 on one side of the circle are unusually crowded together, while 

 those occupying the remainder of the circle are expanded nearly 

 as they ordinarily are. In consequence of this habit of the ten- 

 tacula in the specimens exhibiting these phenomena, I have been 

 uniformly foiled in endeavoring to ascertain whether two mouths 

 were formed simultaneously with the two bases. In one unusu- 

 ally large specimen, however, I observed that what must have 

 been the original mouth of the polyp, was unusually elongated in 

 the same direction as the base. Even in specimens where the 

 process had proceeded to the separation of the bases, I was unable 

 to decide this point. I am inclined to think, however, from what 

 I have detailed above, that the plane of fission does not pass 

 through the central longitudinal axis of the cylindrical body, but 

 a little on one side of it, and by this means a corner only of the 

 mouth, and only a small portion of the stomach, ovarian cavity and 

 circulatory chamber, may be cut off by it ; that is, the new indi- 

 vidual may be less than one-half of the original polyp. 



Jan. 16th. — Observed, yesterday, (15th ult.) that in one specimen 

 (the most advanced), fission had proceeded no further than to divide 

 the tentacular crown into two more nearly equal, but still incom- 

 plete circles. Another specimen exhibited the condition described 

 under former dates. Others exhibited gradual elongation of the 

 base, one of them to an extraordinary degree; but the specimen 

 being attached to the nearly opaque frond of Ulva latissima, I 

 could not see from beneath how far the fission had proceeded. 



A specimen, which, to the best of my recollection, was nearly 

 round at base yesterday, to-night (16th inst.) exhibited a longitu- 

 dinal constriction which did not pass through the axis of the 

 cylindrical body, and which tended to separate a new individual 



