134 Nezv York State Museum 



toward a land existence. The other Periwinkle (L. lit- 

 torea) is found in the barnacle zone in situations similar 

 to those of the Edible Mussel. These two have almost as 

 wjde a distribution as the Acorn Barnacle. The Rock 

 Snail is abundant where barnacles occur, for it feeds 

 upon them. 



Below the barnacle zone, along our North Atlantic 

 rocky coasts, the brown seaweed, Ascophyllum, with its 

 long, matted strands, is to be looked for. There is an 

 abundant fauna here because of the shelter afforded by 

 the seaweed. The Acorn Barnacle is also found here 

 and is abundant. Hydroids are found attached to the 

 rock or on this seaweed in protected situations ; other sea- 

 weeds replace them in more exposed places. Bryozoans 

 or Moss Animals also occur on the Ascophyllum and the 

 rocks. Small crustaceans and worms are numerous. 

 Many animals are attached to the rock under the matted 

 seaweeds. Rock Snails are abundant ; the Common 

 Edible Mussel and Periwinkle (L. littorea) are every- 

 where; the Seaweed Snail and Limpet (Acmaea) are less 

 common. The Rockweed (Fucus) zone is just below 

 this. In protected bays it does not occur and on isolated 

 wave-beaten rocks the Acorn Barnacle and Edible Mus- 

 sel replace it. The most characteristic animals are the 

 Edible Mussel, Acorn Barnacle and Limpet (Acmaea). 

 Other forms that are common are the Rock Snail, Peri- 

 winkle (L. littorea), Seaweed Snail, Common Starfish, 

 a sponge (Cliona), the Jonah Crab (Cancer borealis) 

 the Hermit Crab (Eupagurus pubescens), etc. The zone 

 below starts a little above low-tide mark and continues to 

 a considerable depth. More species are found here than 

 in any other zone. The Irish Moss (Chondrus) which 

 characterizes this zone and forms a thick carpet on the 



