346 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



side chips of metamorphic rocks and schists, but these are 

 all so small and weathered that it is impossible to obtain a 

 fresh surface and thus gain a clue to their true identity. 



Shells and pieces of shells form a very large proportion 

 of the deposit. Excluding the stones, fully .35 % to 40 % 

 of the remainder of the sample consists of the remains of 

 molluscs — from complete valves down to the merest speck. 

 Most of the genera obtained while trawling over this part 

 of the Irish Sea are represented in this deposit. Pecten (many), 

 Cardium, Tellina, Nucula, Trochus, Area, Leda, Emarginula, 

 &c, form the bulk of the unbroken shells, it being impossible 

 to identify the smaller particles with any degree of accuracy. 

 A feature of these smaller shell- fragments is that, almost 

 without exception, their edges and corners are well smoothed 

 and rounded, showing that after the original shells have been 

 broken into pieces of a certain size (probably during their 

 passage through the alimentary canals of fishes and birds), 

 further comminution does not take place. Other organic 

 remains found were pieces of echinoid spines, parts of 

 echinoid shells, polyzoa, and a few Echinocyamus pusillus. 



The true sand of the deposit consists of more or less 

 rounded and very minute grains of pure quartz. The varieties 

 represented are those known as milky quartz and clear quartz 

 or rock crystal. Mingled with the quartz grains are many 

 minute specks of magnetite and mica (muscovite). The latter 

 must be distinguished carefully from the microscopic pieces 

 of the nacreous layer of molluscs which are very abundant. 

 These quartz grains make up the larger part of the deposit. 



Animal life was remarkably scarce in this sample, 

 but I think this may be due to the fact that it was 

 obtained by means of a dredge, which I had rigged up until 

 a Lucas Grab could be obtained. Doubtless when samples 

 taken by the Lucas Grab or by Petersen's " Sampler " are 

 examined the animal life will be found to be more abundant. 



