86 PECTINIDJE. 



depths. Capt. Beechey, however, dredged a living spe- 

 cimen off the Mull of Galloway in 145 fathoms. It 

 occurs fossil in our Red and Coralline Crag. Abroad it 

 ranges from the coast of East Finmark to the ^Egean 

 and the North African coast of the Mediterranean. 

 Asbjornsen gives the depth at which he found this spe- 

 cies living in Christiania fiord as 5-20 fathoms. 



It seldom makes a "nest"; but I have one enclosed 

 in this way, which I dredged on the north coast of Ire- 

 land. The case lies within a valve of Mytilus modiolus, 

 and is composed of large fragments of shells, crabs, and 

 barnacles. Sars obtained a similar specimen on the 

 Norwegian coast. In all probability this habit depends 

 on the nature of the sea-bottom. When the latter is 

 soft mud the Lima can partly bury itself, and does not 

 require to be otherwise protected from its voracious 

 enemies. The haddock seems fond of it, the shells being 

 often found in its stomach. The animal of L. Loscombii 

 differs but little from that of L. Mans. The pallial ten- 

 tacles are somewhat thicker, and the foot is shorter and 

 of a paler hue. Mr. Clark has seen it " repeatedly fix 

 itself by fine byssal filaments, then detach itself and 

 move with the greatest rapidity, crossing a dish of six 

 inches diameter whilst one could be counted." When 

 it crawls it uses its foot in the same way as Modiolaria 

 discors, by extending and attaching the flexible point to 

 the surface of the body it is traversing, and then draw- 

 ing or warping itself up. This mode of locomotion is 

 much slower than the usual one of swimming by a repe- 

 tition of jerks. The fry are ribbed like the adult, but 

 the lines of division between the striae in the former are 

 more remote. 



It is the Pecten fragilis of Montagu but not of Chem- 

 nitz, the L. bullata of Turton but not the Ostrea bullata 



