210 ZOOPHYTES. 



base. Some were still void of any perceptible prominences. An internal 

 organization could be discerned through the side of others. Nineteen days 

 subsequent to production, eight or nine tentacula appeared on one which 

 had then affixed itself by the base, other three of the young animals into 

 which the gemmules had developed were adhering. Of five of the original 

 corpuscula, one was still a minute dark conical figure, a mere speck with- 

 out external organs, each extremity being convex. The remaining four, 

 as just remarked, had fixed : their shape was cylindrical, with originating 

 tentacula, irregular in number and dimensions, — the largest having about 

 twelve, the smallest about seven. 



Thus, whatever may be the form of the Actinia mesembri/anthemum, 

 in its earliest elementary existence, it becomes visible as a ciliated gem- 

 mule, traversing the fluid contents of the distended tentaculum of its pa- 

 rent, and it is sometimes accidentally discharged by the mouth. The 

 utmost irregularity distinguishes its appearance, figure, size, and motions. 

 None of that organization, characterizing its future shape and aspect, meets 

 the view. But its activity relaxes, the cilia decay, or are incorporated 

 with its system, indistinct prominences announce incipient tentacula, it 

 affixes itself securely by the base, and then are due proportions moulded, 

 along with acquisition of additional parts, as the original gemmule is un- 

 folded in a perfect animal. 



Thus will a remarkable correspondence be discovered between the 

 origin and progress of the Actinia, and the earlier and subsequent advances 

 of several of the zoophytes described in these volumes. At first all are 

 endowed with the faculty of progression, speedy in proportion to their 

 size, and the organs effecting it : metamorphosis next succeeds, whereby 

 an animal altogether different in external aspect, structure and habits, 

 succeeds : one which becomes permanently affixed, or which remains for 

 the most part stationary. 



But the external production of the corpusculum is certainly a devia- 

 tion from the ordinary course of propagation. Apparently it ought to be 

 retained until becoming a foetus, during which state it does not neces- 

 sarily occupy the tentacula. No uniformity governs the date or dura- 

 tion of its presence, or its position there ; nor are gemmules to be seen in 



