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THE WORLD OF ANIMAL LIFE 



chalk which the tide has washed together, are dozens and dozens 

 more, very small, but very beautiful. Some are yellow, some gray, 

 some pearly- white ; some are slender, others are stoutly built; some 

 are exquisitely carved and chiselled, others are almost smooth. 

 Yet, different as they are, there is a strong family likeness between 

 them, so that it would hardly be possible to 

 mistake the shell of a whelk for that of any 

 other mollusc. 



Wherever we find whelk-shells, we shall also 

 find the empty eggs out of which they came. 

 These are fastened together in large masses, 

 each about as big as a cricket-ball ; and we may 

 see them lying in numbers upon the beach, 

 or rolling along before the wind on a breezy 

 day. They are yellowish in colour, and not 

 unlike pieces of sponge. 



If you look closely at one of these masses, 

 you will see that each egg is about as large 

 as a pea. When they were laid, however, each 

 was only about the size of a small pin's head. 

 But the membrane which encloses them, and corresponds with the 

 shell of a bird's egg, has a very curious property. It allows water 

 to soak inwards, but not to pass out again. As soon as the egg- 

 ball is dropped into the sea, therefore, each egg begins to take in 

 water and expand. Ere long each has greatly increased in size, 

 and the ball, which was at first so small, has assumed the form in 

 which we are accustomed to see it. 



We have perhaps often noticed other kinds of shells that have 

 a small round hole bored through them, about the size of that 

 which would be drilled by a fine brad-awl. This hole is the work 

 of a whelk, which first pierced the shell, and then devoured the 

 animal inside it. It was done in this way: 



The whelk's tongue is horny, and is set with very small but 

 very sharp and strong teeth from one end to the other. It has 

 several hundreds of these teeth in all, placed in three or four 

 parallel rows. When we examine them by the help of a micro- 

 scope we see that they are most beautiful objects, looking as if they 



Whelk SheU 



