THE EGG-VESICLES. 193 



are of a fine rose colour, and have an attractive 

 appearance. 



The tentacles are endowed with the power of free 

 motion, and they frequently throw themselves to and 

 fro with considerable energy ; when perfectly at ease 

 they are canied projecting at right angles from the 

 polype, hut are more commonly curved up towards it. 

 The whole polype can he also tossed from side to side 

 at pleasure. The tentacles are contractile and exten- 

 sile in some degree ; for if the animal be taken out of 

 water for an instant, and again replaced, these organs 

 are found to he shrunk up to less than half of their 

 former length. In a few minutes they recover their 

 extension. 



Some of the polype heads are furnished with organs 

 of another kind. Among the tentacles, chiefly of the 

 lower whorls, are seen one or two oval bodies, about 

 twice or thrice as large as a tentacle-head, which are 

 attached by short footstalks to the polype-body. They 

 are composed of a clear jelly-like granular mass, with 

 an oval dark nucleus in the centre, connected with the 

 attachment: the nucleus is of an orange or yellow 

 hue, and is coarsely granulated. In some that I kept, 

 this dark nucleus became larger until it almost filled 

 the interior; but the death of the animals prevented 

 my seeing the full development. These are egg-cap- 

 sules, as I afterwards ascertained. 



About the end of August a fine specimen in one 

 of my glasses fell under my notice, as having an appear- 

 ance which made me think that it had just renewed 

 its polype-heads after the old ones had decayed away. 

 But in looking at it I saw that one head bore two 



s 



