MARINE BIOLOGICAL STATION AT PORT ERIN. 119 



through the transverse slit-like opening on the posterior 

 surface of the body into a spacious cavity, in which a 

 pair of plume-like gills is situated. The opening is 

 then closed, and the water forcibly ejected through the 

 funnel — a chimney-like organ, the rounded aperture of 

 which may always be seen projecting to one side beneath 

 the head. These movements, repeated with greater 

 rapidity and force, are subservient also to swimming, the 

 animal being driven backwards at considerable speed. 

 When alarmed or irritated the animal can eject through 



Fig. XXIII. — Eledone cirrosa, the local " Octopus" (reduced to 

 one-sixth of natural size.) 



the funnel into the surrounding water a quantity of inky 

 fluid. This is secreted in a glandular sac which opens 

 into the respiratory chamber, and is similar to the sepia 

 of the cuttlefish. 



The soft skin of the Cuttlefishes is coloured yellow, 

 red and brown by little sacks full of pigment grains, and 

 these sacks can be so varied in shape as to change the tint 

 of the animal in accordance with its surroundings. In 

 little baby cuttlefishes from ^ to \ an inch in length this 

 instantaneous change in colour, or " blushing," can be 

 seen most beautifully as the little animals just hatched 



