SERTULARIA. 141 



parts above and below are in absolute decay, an intermediate branch may 

 exhibit all its vigour in luxuriant efflorescence. In the natural state, the 

 decay commences with the lower ramifications ; in an artificial state, the 

 extremities of the various parts rather seem the first to perish. This cer- 

 tainly ensues with various species, when its rapid progress is always de- 

 structive of the specimen. Nevertheless, the subsistence of vigorous ani- 

 mated extremities may be long, and their reproductions numerous, while 

 all the lower ramifications remain as inert matter, having lost both the 

 vegetative and the vital principle. 



From these reasons, and from constant exposure to accident, as well 

 as the violence sustained in being withdrawn item their native places, per- 

 fect specimens of the Sertularia, always a delicate product, in any but the 

 earlier stages, can be seldom obtained. Almost all have undergone ex- 

 traordinary mutilation. Neither are any of the largest specimens ever ani- 

 mated throughout, so that each cylinder, denticle, or cell, contains a liv- 

 ing tenant. This subsists only in portions of them. Though multitudes 

 remain many have perished : whether from the distempers or casualties 

 incident to the least, as well as to the greatest works of the creation. — 

 Death ensues because life has been. Some elegant specimens, indeed, illus- 

 trate these pages. The reader would be incredulous were I to tell him 

 out of how many rejected, or in the course of how many years. 



The duration of the life of zoophytes is not easily ascertained, espe- 

 cially where an individual of a multitude may be replaced by regenera- 

 tion. If conjectures shall be indulged, it must be from observation of so- 

 litary animals. 



Independently of the preceding injuries from time or accident, the 

 progress of nature itself proves destructive. 



Every compound specimen, even a species which bears a thousand viva- 

 cious hydrae at once, seems to originate through the medium of a single 

 individual animal. The Sertularia, Flustra, Cristatella, Virgularia, and the 

 whole Alcyonic race, exhibit a single polypus, whose existence, in certain 

 genera, is incompatible with the evolution of posterity from the specimen 

 whereof it is the foundation. 



