60 Life Beneath the Waves. 



place to place, in the same way as most other 

 shells, Pectens spring lightly through the 

 water with a series of leaps, caused by quickly 

 opening and shutting their valves, something 

 after the manner of a butterfly's wings. 



The best time to see a Pecten to perfec- 

 tion is after it has been in an aquarium (or 

 any other vessel filled with sea-water), for 

 two or three hours ; its shell will then gene- 

 rally be open about half, or a quarter of an 

 inch, and we find that beautiful as is the 

 exterior of the Sea-butterfly, the live in- 

 mate of the shell is, if possible, still more 

 capable of inspiring us with admiration and 

 interest. When open as just mentioned, a 

 brightly coloured narrow band is visible on 

 either half of the shell, and on the edge of 

 each band is a row of tiny dots of the most 

 brilliant hues, glittering and flashing as 

 brightly as jewels; these dots are supposed 



