THE MUSSEL. 



239 



which it is attached. The great Pinna excels any other in the quantity and fineness of its silk 

 byssus, which has been woven into articles of dress. In early times these were so highly prized as 

 to be worn only by emperors and kings. At Taranto, in Italy, it is still mixed with about one-third 

 of real silk, and made into gloves, caps, stockings, &c., of a beautiful 

 brownish colour. These are valued as objects of curiosity, but too expensive 

 for general use, the price of a pair of gloves on the spot being about six 

 shillings, and that of a pair of stockings eleven. 



A specimen of this manufactured molluscan silk, as well as the raw 

 material, may be seen in the Shell Gallery of the British Museum, beside 

 the valves of the great Pinna. This is one of the largest bivalves, attaining 

 a length of two feet;. It lives from low water to sixty fathoms. 



PINNA XOBILIS, WITH ITS 

 BYSSfS. 



FAMILY V. MYTHJDJE. 



The shell of the Mussel is oval and equivalved, the edges closely 

 fitting, the ligament internal, hinge toothless ; they are mostly marine and 

 attached by a byssus. Some of the members of this family exhibit a 

 propensity for concealment, frequently spinning a nest of sand and shell- 

 i'ragments, burrowing in soft substances, or secreting themselves in the 

 burrows of other shells. Others are gregarious, living in vast beds of tens 

 of thousands clustered together, adhering by their thread-like byssus. 



Genus Mytilus. The " Sea Mussel " has a wedge-shaped shell, with 

 the umbones at the end; it moors itself to piles and stones by a strong 

 and coarse byssus. Mytilus edulis, the common edible Sea Mussel, although 

 far less highly esteemed than the Scallop or Oyster, is nevertheless much 



in request as an article of food. It is difficult to ascertain the consumption of Mussels in London, but 

 in Edinburgh and Leith it is estimated at 400 bushels annually. Dr. Knapp states that from 

 thirty to forty millions are collected yearly in the Fii'th of Forth alone, and used as bait for the 

 deep-sea fishery. They form no small item of consumption in the north of Ireland, boats full being 

 constantly sent to Belfast Market. 



If any one should reflect upon the Mollusca as undeserving so much notice, and mention the 

 Teredo as an instance of a destructive member of the class, let him read of the utility of another, the 

 common Mussel, in maintaining the long bridge of twenty-four arches across the Torridge River, near 

 its junction with the Taw, at the town of Bideford, in Devonshire. At this bridge the tide runs 

 so rapidly that it cannot be kept in repair with mortar. The Corporation, therefore, keep boats 



employed in bringing Mussels to it, and the 

 interstices of the bridge are kept filled with 

 Mussels. It is supported from being driven 

 away by the tide entirely by the strong threads 

 of the byssus which these Mussels fix to the 

 stonework. 



" Mytilus edulis is no friend to the 

 . A colony of Mussels will, unknown 

 to the proprietor of the Oyster bed, often 

 settle upon the spem gregis of ' half ware,' 

 SEA MUSSEL. so carefully deposited to grow fat. The 



Mussels, immediately on settling down, spin 



their curious silk-like webs, as seen under piers, &c., by means of which they are enabled to anchor 

 themselves so firmly. The run of the tide then brings mud, the webs of the Mussels collect it, and 

 the Oysters undei-neath, unless released by the dredge, are smothered like the little princes in the 

 Tower." (Frank Buckland.) 



Mussels are found living in all seas. About seventy species have been described. 

 Genus Jfodiola, the " Horse Mussel," is distinguished from the edible Mussel by its habit of 

 burrowing ; they are met with from low water to 100 fathoms. The shell is oblong and inflated, but 



