50 Quarterly Journal of Conchology. 



drawn from thence OA'er the gills, and are finally expelled from the 

 other tube. Another mollusc, possessing the same boring propen- 

 sities, and worthy of notice, is the " Teredo navalis," commonly 

 known as the ship-worm, somewhat resembling in its external 

 appearance the " Serjnda ;" so much so, that Linnfeus in his " System 

 of l^ature," placed the Teredo between the Serpula and Sabella. The 

 reason why it bears the appellation of the ship-worm is because it 

 has such a powerful appetite for submerged timber, and more par- 

 ticularly so for ship timber. Frequently pieces of oak, the remains 

 of some wreck, have been seen so completely devoured by the Teredo, 

 that it is difficult to discover any portion of the wood that is thicker 

 than any ordinary leaf. As in the case of the " Pholas," the only 

 remedy to preserve the timber from theii* ravages is to have it either 

 pi'otected by closely driven in broad-headed nails, or covered with 

 copper sheathing. The salt water, however, soon causes the nails to 

 rust, and the whole of the timber is now covered with a thick coating 

 of iron rust, which the Teredo appears to have a great dislike to. 

 The common cockle-shell (Cardnmi edule^ is an excellent delver, and 

 armed with his natural spade, digs a hole for himself in the sand 

 almost as fast as a man could dig with a metal sj^ade. The cockle is 

 not only a digger, but is likewise a jumper, and the same insti'ument 

 which serves him as a spade to dig a hole in the sand, also serves him 

 as a foot, by means of which he is enabled to make a spring into the 

 air. Yet another buiTowing shell, which can be picked up almost 

 any day on any of our sandy beaches, and that is the Razor-shell 

 {Solen ensis). This creature biu-rows even deeper than the cockle, 

 frequently being found at a depth of two feet. Generally, however, 

 it prefers remaining sufficiently near to the sui-face to permit the tube 

 just to protrude from the sand. The burrow in which the animal 

 lives is almost perpendicular, and in it the Solen passes its entire 

 life, sometimes ascending and sometimes descending ; for, bear in 

 mind, it possesses none of those locomotive faculties with which its 

 fellow delver, the cockle, is gifted. The activity of its movements 

 compensates in some degi'ee for its range of travel being somewhat 

 circumscribed, and its habitation likewise so narrow. 



GosFORTH Grove, near Newcastle-ou-Tyue, 

 November ISth, 1874. 



Simultanecus Occurrence of Five Sinistral Examples of Helix 

 aspersa — When I was quite a small boy I was told to look out 

 for a snail that turned the wrong way, meaning a sinistral form of Helix 

 aspersa. For forty years or upwards I never killed a snaU of any kind 

 without carefully examining it first, and was never successful. But in 

 the year 1865, a labourer working in Moss's nursery gardens here 

 (Epsom) found two examples, evidently only of that year's growth, that 

 is, they were about the size of large peas. I reared them to maturity 

 under a glass shade. The following summer I found an adult example 

 feeding on a cauliflower in the garden of my friend, the late Joseph 

 Ward, Esq., and a fourth example I received from Little Bookham, 

 a village about eight miles from this place ; and the following winter 



