ACTINIA. 211 



the majority of the tentacula. As many as eight may appear in one : and 

 in another some embryos may be intermixed with some of the foetus far 

 advanced. 



In respect to all these facts, the greatest irregularity prevails through- 

 out. 



The period of gestation is long : and, by a strange anomaly in the 

 animal economy, it is, beyond any question, arbitrary. Embryos have 

 appeared in the tentacula five months preceding their birth : eight months 

 have intervened between the production of two successive broods. An 

 Actinia, as alluded to in the following paragraph, taken in autumn 1805, 

 produced two young after a year's captivity, and a third in April 1807. — 

 Plate XLVI. fig. 4. 



The transparence of the distended tentaculum exposes the embryos 

 in all their different stages, some very minute, others obviously too large 

 for their prison : and many so mature, that not only incipient prominences 

 are seen, but the tentacula of the farthest advanced can be enumerated. 

 Yet, the largest are not the first produced ; they may be preceded by many 

 of much smaller dimensions. 



Assuredly none have any adhesive faculty during retention, other- 

 wise they could be scarcely withdrawn at pleasure, as occurs continually, 

 and for an indefinite time. Those once seen may be never seen again 

 under the same conditions ; for neither the same embryos, nor the same 

 number or distribution of the tentacular contents, are returned after 

 having been withdrawn. 



During a genial evening of June, a nascent Actinia was found re- 

 versed immediately under the site of the parent, which, though greatly 

 contracted, and the mouth protruding in a conical form, still retained its 

 horizontal position. It had been fed on the preceding day, and was now 

 casting its skin, as very common after repletion. But, being relieved of 

 the slough, instead of expanding as usual, it remained compressed, the 

 tentacula flaccid, small, and empty. 



In half an hour three minute organs were issuing from the mouth ; 

 more came in view ; — I recognised them as tentacula ; and in another 

 half hour a large foetus was expelled, which, falling to the bottom, lay re- 



