CHITON. 137 



The sketch exhibits one of these creatures reclining 

 on a piece of rock. It is drawn from nature, but 

 appears somewhat different from the usual represen- 

 tations, in respect that the fan seems to open from 

 a double centre, and that the stopper is under the 

 expanded plume. It struck me as being rather a 

 surprising fact, that from the centre of the stopper, 

 there sprung a small frond of dulse. How this 

 managed to become attached to such an extremely 

 sensitive organ, I am at a loss to imagine. 



There is another class of annelids, nearly allied to 

 the above, named Sabdlce. 



Their tubes are formed of sand, and are found 

 generally congregated around the edges of the rock- 

 pools, among the weeds. It is easy to detect their 

 presence from the number of holes that appear to 

 have been newly bored, as if with a small brad-awl. 

 They are by no means suitable objects for an 

 Aquarium, as they do not live long in confinement. 



On turning over almost any piece of stone, such as 

 those to which the Serpula affixes its tubes, a strange 

 creature, something like a Wood-louse, will often be 

 met with. This animal, which is known as Chiton, 

 is not very pretty to look at; and I merely mention it 

 here, because it is common, and because it holds a sin- 

 gular position in the marine animal kingdom. While 

 the majority of its brethren, such as the Patellae, &c., 

 have their bodies protected by a testaceous shield, 

 the covering of the Chiton consists of eight shelly 

 plates, or scales, that overlap each other like slates on 



