464 



DEPTHS OF THE OCEAN 



The fully developed individuals of Metriduuu are usually found 

 in places where there is a strong current. 



Off the coasts of Scandinavia the sandy bottom of the 

 low-tide area is not so extensive as along other coasts of the 

 North Sea, but it is interesting to note that the fauna inhabiting 

 this region is much the same everywhere, and that burrowing 

 forms predominate. There is first the sandgaper i^lMya 



Fig. 322. 

 Actinia equina, L. 



arenaiHa), and then the cockle [Cardmm ediile, see Fig. 324), 

 and also different species of Tapes, though these are not so 

 universally distributed. The lugworm [Arenicola piscatorum, 

 see Fig. 325) is another burrowing form, and its presence can 

 easily be detected by little heaps of string-like excrements. 



In addition to these forms, which are adapted for life in 

 the low-tide area at those parts of the coast where the ebb-tide 

 recedes a long way, we also get the common shore crab 

 {Carcimis moeiias), often to be found under fucus that has been 

 left exposed. This is the case also with the common starfish 

 [Asterias itibens), and occasionally, too, with the common 



