124 THE AQUARIAN NATURALIST. 



is more than possible that these polyps may be en- 

 dowed with a power of seizing and devouring prey of 

 a higher description, as is known to be the case with 

 their great prototypes, the Hydrge properly so called. 

 We at least invite the attention of the observer to 

 this part of their history, about which naturalists are 

 at present much in the dark. 



Whilst experimenting on a specimen of Sertularia 

 (Plumularia) falcata, Sir John Dalyell observed a 

 very remarkable circumstance in the economy of these 

 zoophytes. Having cut some specimens near the 

 root during the month of December, and subdivided 

 the severed stalk of each into several portions, he was 

 surprised to observe vigorous reproduction ensue from 

 both extremities of each of the separated fragments; 

 all the new stems thus produced becoming in the 

 course of a few days furnished with numerous hydri- 

 forrn polyps, and evidently capable of continuing this 

 mode of increase to an indefinite extent. Every part 

 of the zoophyte would therefore seem to be endowed 

 with vital energy quite irrespective of the rest. 



The life of the specimen is dependent on the sub- 

 sistence of the pith : the life of each individual polyp 

 on its connexion with the common stem. The life of 

 each of a thousand Hydrse, though all supported on 

 the same polypary, and rising from the same root, is, 

 however, quite independent of that which animates 

 all the rest, and the death of no one individual seems 

 to aflect its neighbour. While the parts above and 

 below are in absolute decay, an intermediate branch 



*/ ' 



may exhibit all its vigour in luxuriant florescence. 

 In the natural state the decay commences with the 



