108 A NATURAL HISTORY OF THE SEAS 



on the other hand, are washed up in immense numbers 

 upon all tropic and sub-tropic beaches. 



The Cephalopods known as Squids are, broadly, different 

 from Cuttlefish in having the internal shell composed of 

 translucent horny material, whilst in the latter it is of a 

 limey and calcareous nature. All Squids have ten arms, 

 eight being of more or less equal length, whilst the two 

 long arms may exceed many times the total length of the 

 entire animal, and have suckers arranged on clublike 

 extensions of the tips. 



The short arms bear two rows of suckers throughout 

 their entire length. Each sucker is mounted on a short 

 stalk and has its outer rim strengthened by a horny sub- 

 stance, which in many species is composed of numerous 

 stout hooks ensuring a tenacious hold upon anything it 

 touches. The horny beak is similar in construction 

 throughout the group ; whilst the eyes have large and solid 

 crystalline lenses. 



Both Squids and Cuttlefish are of some economic value. 

 Vast numbers are used as food and bait, and in the former 

 capacity have masqueraded as tinned lobster. The eye- 

 lenses have been used in ornaments, the ancient Egyptians 

 employing them as eyes for their mummies. Large 

 numbers of Squids are eaten by certain whales and the 

 cetaceans' digestive fluids convert the horny beaks into the 

 valuable ambergris to be mentioned more fully in the 

 chapter on mammals. The limey shell of the Common 

 Cuttlefish {Sepia officinalis) is often given to cage-birds, 

 and also forms the basis of many powders used in pharmacy. 



Finally, the ink has been almost universally employed 

 for writing and painting, immense numbers of dried ink 



