MYTILUS. 107 



out of water. Young shells of M. edulis are coated with 

 short bristly hairs, and resemble in shape those of M. 

 modiolus. They grow very rapidly. According to Mr. 

 Clark, if the fishermen's lobster-pots are left for a week 

 or two in the autumn, they will be covered with mussels 

 more than half an inch long. M. Bouchard-Chan- 

 tereaux has often watched this mollusk in the act of 

 spinning its byssus. He says that when put into a 

 vessel of sea-water, it first creeps along the bottom by 

 means of its foot and tries to ascend the side. After a 

 while it deposits from the end of its foot a speck of white 

 transparent matter, which spreads out and immediately 

 hardens like china-cement. This plate serves as a base 

 of attachment ; and from the centre of it the mussel 

 secretes very slowly and by a backward movement a 

 gluey thread, repeating this process ten or twelve times 

 in a circular direction. The threads become horncolour 

 in from twenty-four to thirty hours after being spun. 

 It is said to have the power of contracting its byssus at 

 will ; but I should be inclined to doubt it. The mussel 

 is on the whole a respectable and stay-at-home cha- 

 racter, seldom leaving its place of abode unless it has 

 been dislodged by an unusually boisterous wave or by 

 the equally rude and violent hands of man. Charles 

 Lamb speaks of its " dignified leisure," while traversing 

 the circuit of two inches square, within which it swings 

 by the aid of its elastic cables. When confined in a 

 prison called an aquarium, it appears to be more rest- 

 less than in its native haunts, perhaps trying to escape 

 from the unaccustomed quarters in which it finds itself, 

 and in vain awaiting the welcome refluence of the 

 tide. It may then be observed making occasional jour- 

 neys from one part to another, and leaving at every 

 stage or halting-place a bundle of filaments attached to 



