A WALK ALONG THE SHORE. 99 



we have already considered, so 

 we pass on to a group of strong, 

 black shells whose owners have 

 met together on the sheltered 

 side of a big rock. They are the 

 Turban-shells, and there are va- 

 rious species of these, also, — Figure 51. 

 Black Turbans, Brown Turbans, Red Turbans, 

 and Blue Turbans, as well as others which you 

 do not often find. 



The Black Turbans are by far the 

 most numerous. You see a picture of 

 one in Figure 50. Their shells are 

 strong and heavy, enabling them to 

 resist the knocking of the waves. In- 



Figure 512. sidc, they are beautifully pearly, like 

 the abalone. The aperture is closed by a circular, 

 horny front door. 



The little black animals are vegetable-eaters, 

 like the littorines, and they as- 

 sist greatly in keeping the rocks 

 clean and fresh. 



A little nearer the water are 

 tlie Brown Turbans (Figure 51).( 

 In fact, they seldom come up far 

 from the lower tide limits, though 

 you may find them alive in caves Figure 53. 



