102 MYTILID^E. 



requires five or six hours' stewing, and then is not so 

 tender as a scallop. The fibrous particles which com- 

 pose the shell are crystalline, and very beautiful objects 

 for the microscope. Mr. Spence Bate informs me that 

 the trawlers at Plymouth call these shells "eaper- 

 longers," and that they avoid the Pinna-ground for fear 

 of their nets being torn. The shells are described as 

 standing upright on their narrow end, and as bearing 

 some resemblance to trees in a thick forest. The word 

 "caperlonger " appears to be a corruption of Cappa lunga, 

 by which name the Pinna is known in the Mediter- 

 ranean. So many of our men-of-war have been at 

 Naples, that the familiarity of Plymouth seamen with 

 such Italian words is easily explained. 



Owing to the variableness of its sculpture and solidity, 

 this species has received many names from British con- 

 chologists, viz. borealis, pectinata, fragilis, muricata, 

 ingenSy l<evis, papyracea, rotundata, and elegans. It 

 may, however, be observed that the P. muricata of 

 Linne has never been found in this country, and that 

 " India" is stated to be the habitat of his P. pectinata. 



Family V. MYTI'LID^E, Fleming. 



Body thick and rather convex : mantle more or less open in 

 front, and usually folded on the posterior side into a wide ex- 

 current tube or slit : foot shaped like a strap or worm, and 

 having a byssal groove. 



Shell obliquely oblong, oval, or rhomboidal, equivalve, in- 

 equilateral, and covered with an epidermis : beaks incurved : 

 ligament long and narrow, mostly internal, and contained in a 

 groove. 



The Mussel family differs from the last in the mantle 

 not being open throughout, but having its edges united 



