16 WEST COAST SHELLS 



the omission of a fraction. This shell is not a com- 

 mon one, but is reported as occurring from Mon- 

 terey southward. The groundwork of the shell is 

 white, and there are ribs of carmine. 



The appearance of ^ere- 

 hratalia transversa^ Sby., the 

 Red Lamp-shell, is well 

 shown in Figures 5 and 6. 

 It is by far the most common 

 species of the brachiopods to 

 Fig.5,xH*) be found on our coasts. It 



attains its highest development in the cool waters 

 of Puget Sound, where it sometimes grows to a size 

 much larger than that of the picture. On the east 

 side of Vancouver Island it 

 is reported to be found in 

 thousands, attached to the 

 rocks. From that point it 

 extends both northward and ^'^^- ^' "^ ' ^*^ 



southward, having been found from the frozen Aleu- 

 tian Islands of the Arctic to the sub-tropical Cata- 

 lina Island of California. It can sometimes be col- 

 lected about San Pedro at very low tide. Note that 

 the central scallop on the edge dips downward in 

 this shell, while in the last species it bends upward. 

 The general color is red, though in some specimens 

 a considerable part of the shell is white. It makes 

 a very pretty specimen for the cabinet. 



haqucus calif orniciis^ Koch, the California Lamp- 

 shell, Figure 7, is entirely different from the last 

 species, the shell being very thin, smooth, and free 

 from wrinkles of any kind. If you turn the figure 



