58 HABITS OF THE CEPHALOPODA. 



head with the trunk. The tentacular arms remain contracted 

 within the others when in repose; a position difficult to under- 

 stand, as after death they are found to be more than double the 

 length of the sessile arms. Sometimes the first pair of arms 

 are raised into a vertical position, like a ntenme, the others pre- 

 serving their normal attitude ; sometimes, also, the fourth pair 

 of arms drop towards the earth for a few moments, and much 

 elongate themselves. 



The coloring of the Sepia is eminently variable; but if the day 

 is clear, the dorsal surface and arms are magnificently siripcd; 

 the edges of the fins are black, and their superior face is orna- 

 mented with spots of the same color. On the back of large indi- 

 viduals is seen two large obscure spots, which vary in intensity 

 and sometimes entirely disappear. The eye is fatigued in fol- 

 lowing the incessant variation of coloring caused by the constant 

 movement of the pigment cells, and the metallic reflections of 

 the head and arms are glorious beyond human skill to reproduce. 

 The skin is usually smooth; but when the animal becomes irri- 

 tated, it shows granulations, principally on the head and back. 

 This is accompanied by a retraction of the arms, which appear- 

 both shorter and narrower; the extremities no longer touch, but 

 curve slightly. At the same time the colors change, a uniform 

 gray tint takes the place of the striped bands. The approach of 

 death is equally announced by a change of colors, which grow 

 dull. 



The swimming of the Sepia is differently effected, according. to 

 the speed required. A moderate progression is equally easy 

 forwards or backwards. When the animal moves forward, the 

 body remains horizontal; the tentacles, united and extended in 

 front, rest on the fourth pair of arms. The Sepia follows in this 

 manner the course of the water, the resistance of which bends 

 the extremities of the united arms. A moderate backward move- 

 ment is effected in the same manner; but the tentacles are more 

 elongated and their extremities are somewhat parted; the arms 

 are raised to the line of the body. The undulations of the fins 

 commence at the front or rear, according to the direction which 

 the animal takes. This method of swimming, due cntirelv to the 

 fins, is not slow, for the normal movement of the Sepia is easy. 

 elegant and rapid; but an occasion of disquietude, as the sight of 



