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division of the mollusca, whose habit is to penetrate either sand, as 

 the common cockle, Cardium edule or wood, as the different species 

 of Teredo or stone, as the genus Pholas, a bivalve, of which the shell 

 in some species is extremely fragile, and although wonderfully well 

 adapted to its work as an excavator of solid rocks, requires the utmost 

 caution when being handled in our collections. The species that 

 bores through the sandstones at Lamlash is Pholas crispata. The 

 wood-borer, Teredo navalis, is common in many parts of the Clyde, as 

 may be proved by witnessing its destructive operations at Ardrossan 

 and Fairlie on the Ayrshire side, where also its ally, Xylophaga, 

 dorsalis, has done its full share of mischief. Another species, less 

 common, and of larger growth formerly unknown, as is supposed, 

 higher up the Clyde than Port Patrick, viz., Teredo Norvegica, 

 introduced itself into Lamlash bay, and, during the short period of 

 about seven years, it had almost demolished the massive supports 

 of the pier a commodious and substantial landing place, erected, 

 as the owner undoubtedly thought, for the convenience of himself 

 and friends. The Teredo, however, commenced and continued its 

 operations unnoticed not one pile of the water-covered timber 

 escaped the whole was pierced in lengths varying from a few inches 

 to about two feet, when, in the hurricane of February, 1856, a vessel 

 was driven upon the spot, and almost the entire structure was swept 

 away.* On an examination of the fragments thrown upon the 

 island, several specimens of the calcareous tube, formed by the animal 

 in the course of its progress, and a few of the valves, were secured 

 for private cabinets ; and pieces of the bored timber were given to 

 the museums of Glasgow College and of the Andersonian University. 

 The most abundant species of Trochus on these western shores 

 is T. umbilicatus, which, with T. dnerarius and T. tumidus, may 

 be procured in any quantity on Holy Island. Here also the following 

 shells are not uncommon: Acincea testudinalis, Kellia rubra a 

 minute bivalve attached to the dark low growing plant, Lichina 

 pygmcea, which overspreads the rocks near the sea ; Patella athletica, 

 P. pellucida, Tapes decussata, with different species of Littorina, 

 and other equally common and widely diffused forms. In the 

 sands, at Lamlash, at low water, Mactra solida, and M . subtruncata, 

 are plentiful. But, leaving the coast line, and letting the dredge 

 drop in about ten fathoms, at the north end of Holy Island, or 

 between the north point of the island and the pier, a peculiarly 

 interesting shell may be collected in large quantities Lima hians, 



* This pier was built by the late Mr. Oswald, member for the city of Glasgow. 



