Fig. 184.—Loligo vulgaris and its Pen

Fig. 185.—Sepiola atlantica

The Common Calamary (Loligo vulgaris) may be recognised by the accompanying illustration, from which it will be observed that the body tapers behind, bearing two rhomboidal fins in the rear. The suckers are arranged in two rows on the arms, but in fours on the expanded tips of the tentacles. The animal is a good swimmer, and sometimes crawls, head downwards, on the disc surrounding the mouth, pulling itself along by means of its arms. Its shell is a horny pen, lanceolate in form, but it divides as the age of the animal advances, so that two or more may be found in the same specimen.

Belonging to the same family we have the Common Squid (Sepiola atlantica), also a very abundant species. Here the body is shorter and purse-like, and the fins are dorsal and rounded. It seldom exceeds four or five inches in length, and, like the Calamary, is used largely as a bait by fishermen.

Another family—the Sepiadæ—contains the Cuttlefish (Sepia officinalis), the ‘bone’ of which is such a common object on the beach. This latter is a broad, curved plate of carbonate of lime, made up of a number of regular layers, and having a cavity hollowed out at the posterior end. It is exceedingly light and porous in structure, and at one time was used largely as an antacid as well as a dentifrice. It is also proportionately large, being both as long and as broad as the body of the animal.