276 THE INHABITANTS OF THE SEA. 



be remembered that their body is soft and naked, and that, 

 though well armed in front, they may readily be attacked in the 

 rear. To afford them the additional protection they required, 

 nature, ever ready to minister to the real wants of her children, 

 has furnished them with an internal bag communicating with the 

 respiratory tube, and secreting a large quantity of an inky fluid, 

 which they can squirt out with force in the face of their foe, 

 and which, mixing readily with the water, envelops them in an 

 opaque cloud, and thus screens them from pursuit. But this 

 inky fluid, thus useful to its owner, is often the cause of his 

 destruction by man, who applies it to his own purpose, for 

 the Italian pigment, called sepia, so invaluable to painters in 

 water-colours, is prepared from the inspissated contents of 

 the ink bag of a cuttle-fish. Such is the durability of this 

 colour that even the inky fluid of fossil species has been found 

 to retain its chromatic property. We are told that grains of 

 wheat buried with Egyptian mummies three thousand years 

 ago have germinated ; but it is surely still more astonishing 

 that an animal secretion, the origin of which is lost in the 

 dark abyss of countless ages, should remain so long un- 

 altered. 



The cephalopods are scattered in vast numbers over the 

 whole ocean, from the ice-bound shores of Boothia Felix to the 

 open main; they seem, however, to be most abundant in 

 temperate latitudes. Some, like the common poulp, constantly 

 frequent the coasts, creeping among the rocks and stones at the 

 bottom ; others, like the Cirroteuthis and Ommastrephes, roam 

 about the high seas at a vast distance from the land. 



They are generally nocturnal or vespertine in their habits ; 

 they abound towards evening and at night on the surface of the 

 seas, but sink to a greater depth, or retire into the crevices of 

 the rocks, as soon as the sun rises above the horizon. Some are 

 of a recluse disposition, and lead a solitary life in the anfrac- 

 tuosities of the littoral zone ; others, of a more social temper, 

 wander in large troops along the shores, or over the vast plains 

 of ocean. 



Possessing the organs of sense, and the means of locomotion 

 in a high degree of development, the cephalopods may naturally 

 be expected to be far more active and intelligent than the 

 inferior orders of the molluscs. On moonlight nights, among 



