244 ZOOPHYTES. 



of its progeny also surrounded this hydra when it had survived 237 days as 

 an independent animal, fig. 2. 



On January 17, a favourable view enabled me to ascertain that its 

 long, flowing, silky tentacula, amounted to sixteen. 



From its increasing dimensions and fine condition, I was induced 

 to expect early promise of the medusan roll. Prominent indications of 

 progeny appeared on February 7, fig. 3, which were stronger in a fortnight 

 by the germination of three young hydra with originating tentacula, fig. 4, 

 whereby and the preceding figure the individual is seen singly, but slightly 

 exceeding nature. 



The proper breeding season was now passing away. The animal had 

 been fed abundantly, and very carefully treated ; it had grown much, and 

 was in great vigour. But my expectations of the medusan roll were 

 utterly disappointed — nothing of the kind ensued. Progeny continued to 

 germinate from the side without the smallest semblance of Medusa? on 

 the disc. Many of the same original colony affording this specimen had 

 been also preserved, though none of them treated with equal care ; in re- 

 spect to which also, the season elapsed without the metamorphosis of any. 



On April 11, above a year from liberation of the Medusae, the sub- 

 ject of this notice, with four of its germinating young, and surrounded by 

 fourteen free, is represented fig. 5. 



Thus it appeared that the metamorphosis of a hydra developing from 

 a bulb, which had been the site of a roll dissolving in Medusae, did not 

 necessarily contribute to the formation and resolution of the like on arrival 

 of the proper season in the following year. 



Neither was it proved that the hydra having once undergone such a 

 metamorphosis underwent it again : which was in conformity with the in- 

 ference previously deduced from colonies and their descendants having re- 

 mained for years unchanged. 



A fellow naturalist, residing at about the distance of 200 miles, hav- 

 ing acquainted me that a colony of hydrae, whereon he was engaged, had 

 perished accidentally, thus interrupting his progress, I hastened to supply 

 the loss. The pecten, originally bearing about 110 hydrae, was now broke 

 down, and one of the pieces, with a sufficient number, being dispatched 



