252 WEST COAST SHELLS 



large, oblong hole, and roughened ribs. The mar- 

 gin is crenulated, the interior white, and the exterior 

 gray or marked with dark rays; the length is 19 

 millimeters. 



Megatebennus bi??iaculatui^ Dall, the 

 Spotted Keyhole-limpet, Figure 251, was 

 Fig. 251 formerly called FissurelUdaa h'unaculata. 

 These long names apply to a little shell 

 which occasionally grows to a length of 16 mm., 

 though many specimens are much smaller. The hole 

 is very large for the size of the shell, and on either 

 side of it are dark rays, making the two spots, from 

 which circumstance it is named. Sometimes the 

 whole shell is colored, with darker rays on the sides. 

 The interior is white, though sometimes the spots 

 show through. This species is reported from British 

 Columbia as living on the rootlike holdfasts of the 

 great seaweed, Macrocystis. It also occurs much 

 farther southward, though it is a comparatively rare 

 shell. The animal is much larger than the shell, 

 part of which is concealed by the mantle. 



There are very odd creatures living under the 

 stones which lie along the rim of the ocean. If you 

 go down at low tide and turn the rocks over, one by 

 one, you will be surprised at the number of singular 

 beings which stare up at you in blank amazement, 

 and then rush awa}^ into obscure places, as fast as 

 their ten or fourteen legs will carry them. Others 

 cannot run, but in sheer helplessness wait for your 

 kind decision to do them no harm, and their very 

 inertness ap[)eals to your sympathies. While the 

 saucy crabs waste no time in ceremonies, and the 



