176 NATURAL HISTORY. 



broad white stripes, many of which, usually alternate ones, bifurcate at each end, the interspace* 

 being rich vandyke-brown ; between them and the lateral fin the skin is tinged with tawny and 

 irregularly spotted. The fins themselves are brownish above, minutely speckled with white ; a white 

 line runs parallel with the edge, which is itself bounded by a minutely speckled, very narrow border. 

 The neck is white, with greenish and rosy reflections. The back of the head and arms are rich brown r 

 becoming faint and passing into specks on the sides of the latter. The 

 eyes are black. The tentacular arms are white, with a few pinkish-brown 

 dots. The entire under surface is bluish-white, with rosy specks. No figm-e 

 that we have seen gives a true idea of the rich painting of the common Cuttle- 

 fish. The female is wider than the male. The " bone," or shell, is thick, but 

 depressed to an ovate-oblong form, varying a little in shape in different 

 examples ; it is very regular and symmetrical, smooth and corneous at the 

 sides, and more or less furrowed and rugose over the greater part of its surface. 

 Near the posterior extremity is seen the hard mucro. It is most prominent 

 in young specimens. The under surface is convex, depressed and hollowed 

 out at the sides behind. The margin projects widely below, and curves 

 upwards and inwards, and expands in a wing-like form below around 

 the nucleus of the shell. The substance of the "cuttle-bone" is composed 

 of numerous shelly laminae, separated from each other by a perpendicularly 

 fibrous calcified tissue, exhibiting a shiny white and satiny lustre, and having 

 COMMON CUTTLE. a p um i ce ous aspect and feel. Thus extreme lightness, in proportion to its 



bulk, is given to this body. 



The bone equals the body in length, without the fins. A full-grown Cuttle-fish measure* 

 ten inches in length. The breadth of the body is six inches. The arms are five inches in length, 

 and the tentacles a foot and a half long. 



This animal seems to be generally distributed around the shores of Britain. It is scarce to the 

 north of the island, more common to the south, and exceedingly abundant in the Mediterranean. 

 The eggs are dark, oval-shaped, with prominent summits, and have a membranous ring at their bases,. 

 by which they are attached to sea-weed, or fixed to each other so as to form masses of considerable 

 numbers.* 



Although, as already seen, we are no longer studying animals belonging to the vertebrate 

 classes, but to the invertebrata, nevertheless we find, besides the internal shell of the Cephalopoda, 

 that the principal nerve-mass, or " supra-cesophageal ganglion" (so called because it is placed 

 above and around the gullet, or oesophagus), is protected by a thick cartilage, which extends in 

 different directions, so as to afford a basis of attachment to the chief muscles of the body, thus 

 serving in lieu of an internal skeleton. It is most largely developed in the Dibranchiate division, 

 and especially so in the Cuttle-fish. In the Cuttle the cranial cartilage completely surrounds the 

 gullet, and expands above into a cavity to protect the brain, is hollowed below into cavities to- 

 form organs of hearing, and at the sides to give support to the back part of the orbits. The 

 long lateral fins are each supported by a narrow flattened plate of cartilage, to which the 

 powerful fin-muscles are attached by fibro-cartilaginous laminae, resembling those which support the 

 fins of the cartilaginous fishes, such as the Ray. (Owen.) There is a strong muscular heart in all 

 the animals belonging to this class, which, when single, is always systemic. Besides the aortic or 

 systemic heart, which has only one cavity or ventricle, each vessel leading to the gills has a dilated 

 contractile portion, which dilatations may be considered as branchial hearts, so that there are three 

 separate contractile portions of the circulatory system. 



" The common Cuttle-fish, often called by sailors the ' Scuttle,' when seen alive, is a lovely 

 object. Unlike the skulking, hiding Octopus, but equally rapacious, it loves the daylight and the 

 freedom of the open sea. Its predatory acts are not those of a concealed and ambushed brigand 

 lying in wait behind a rock, or peeping furtively from within the gloomy shadow of a cave, but 

 it may better be compared to the warlike Comanche vedette, seated motionless on his horse, and 

 scanning from some elevated knoll a wide expanse of prairie, in readiness to swoop upon a weak 



* Forbes and Hanley : " British Mollusca." 



