THE SMALLER SEA-SHELLS 



191 



Fig. 182 



then pause and build up a thick 

 lip. Leaving this ridge it goes 

 on and completes the whorl, and 

 then forms another varix. The 

 result of this singular mode of 

 building is a shell with two 

 ridges extending from the apex 

 to the canal, on opposite sides of 

 the whorls, giving the front of 

 the shell a somewhat flattened 

 appearance. The external color 

 is yellowish brown, but within it 

 is white. The common length of one of these shells is 

 three inches, though some of them grow to twice 

 that length, and thus rank among our largest shells. 

 Figure 183 gives us a somewhat enlarged repre- 

 sentation of Pedicularia calif ornica^ Newc, the Cali- 

 fornia Pedicularia. In this shell the aperture and 

 outer lip are greatly extended, and the 

 spire is completely hidden. The inside of 

 the shell is smooth and glossy, but the out- 

 side is slightly roughened. With the aid 

 of a microscope one may see a fine system 

 of minute lines and meshes. Its color is peculiar for 

 a shell, being a rich, rosy pink, very beautiful. These 

 little shells are found on the stems of sea-fans, popu- 

 larly known as corals, which are brought up from 

 tolerably deep water. To these they cling like a 

 parasitic insect; hence their name, which really 

 means louse-shell. When fully grown the shell may 

 be nearly half an inch long, though most specimens 

 are much smaller. 



Fig. 183 



