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pyloric coecum, which is often large and spiral. (In the 
Nautilus the oesophagus dilates into a pear-shaped crop, which 
is joined to the gizzard or stomach by a short canal.) In all 
Cephalopods the liver is of large size, and the two hepatic 
ducts connect it with the pyloric coecum ; from the pyloris 
the intestine is continued by a neural flexure (that is with its 
bend towards the principal nerve centres, and away from the 
heart), and ends in an orifice (the anus) in the mid- ventral 
region. The hepatic ducts are clothed with peculiar glandular 
bodies, which are supposed to be pancreatic in their functions. 
The Ink-hag is only found in members of the Dibranchiate 
order, it is a sac-like body, invested with powerful muscles, 
contained in a thin silvery skin, and secretes an inky fluid 
which its owner can expel at pleasure, and by discolouring 
the surrounding water can often escape from those who seek to 
capture it. The ink-bag is situated in the postero- ventral 
portion of the body, and opens by an orifice near the anus. 
The Cephalopoda are carnivorous, feeding upon Crustacea 
mollusca, and even fish. Professor Owen found in the 
stomach of the Nautilus, from Marekini Bay, the remains of 
Si, non-swimming Crustacean. Dr. Macdonald says that the 
Fijians esteem the pearly Nautilus very highly, as an 
agreeable viand, and capture it in basket-traps, baited with 
boiled cray-fish (Palinurus), and sunk amongst the ledges of 
rock or coral, which it is known to haunt. 
The Circulatory and Respiratory Systems. — A true 
systemic heart, consisting of a single ventricle, receives the 
colourless blood from the gills, and passes the aerated liquid 
to the body; there are, also, accessory contractile organs, 
corresponding in number with the gills, these are branchial 
hearts or auricles, and pass the blood into the heart ; they 
are situated at the foot of each plume-like gill ; in the 
Dibranchiata a capillary system obtains, connecting arteries 
and veins. 
