THE MOLLUSCA. 131 



it is now more abundant four or five miles to the west, at 

 high-water mark. 



Tornatella fasciata. Very abundant. Not unlike a shuttle in 

 shape, but broader in proportion, and beautifully coloured 

 with bands of pink and white. 



Scaphander lignarius. Many years ago this was not an un- 

 common shell on our shore ; it is now extremely rare. 



Philine aperia. Common. An extremely thin, white, trans- 

 lucent shell, without spire, and a wide open mouth. 



CEPHALOPODA DIBRANCHIA TA. 



SEPIADjE. 



Sepia officinalis (the Common Cuttle-fish). The internal shell 

 of this mollusk is occasionally washed up in considerable 

 numbers during heavy gales in the winter. It is six to 

 eight inches long, three inches in width, oval, and ex- 

 tremely light in proportion to the bulk. The class Cepha- 

 lopoda ranks the highest in the mollusca, as in the 

 complexity of its organisation it approaches most nearly 

 to the vertebrated animals. It is named from the loco- 

 motive organs being arranged round the head ; when in 

 the water, or crawling amongst rocks or on the strand, the 

 animal has the appearance of being head downwards. 

 The Sepiadae have eight short lanceolate, and two long 

 tentacular arms. The large and prominent eyes are 

 situated underneath the arms, one on each side ; above, 

 in the centre of the circle of arms, is a strong horny beak. 

 The arms and tentacula, besides being organs of loco- 

 motion, serve to catch and hold their prey ; and, as they 



