160 FOOD FOR THE POMPANO. 



threads of nerves and muscles which, if you have a magnifying glass, you 

 can trace running up and down the walls of the transparent tube ; and its 

 use is to act as a screen. You can prove this very plainly if you let a 

 donax bury his shell as he likes to do. A moment later you will see a 

 small white head pushed just above the surface, and this beautiful feath- 

 ery circlet opening and shutting, throwing aside the shining grains of sand 

 that float upon it, or clutching with eager grasp some soft morsel and 

 passing it within. At the same time, close beside it, protrudes very 

 slightly from the sand another tube-head, but here there is only a ragged 

 edge instead of lovely fringes; and out of this tube bubbles up a perfect 

 little fountain of waste water, tossing forcibly aside any floating stuff that 

 comes opposite its aperture. 



One of the most striking things about our wedge-shaped pet is his 

 strength. That soft, thin foot has such power that with it he can nearly 

 stand upright, and can dig swiftly through the most compact sand. He 

 can force a stream of water out of his hose-pipe which will plough up the 

 bottom ; and, by means of his small internal muscles, can hold his shell- 

 coat so tightly buttoned that only with the greatest difficulty can my 

 giant-fingers pull it asunder. 



When the sun goes down, or when the water gets cold, the donaces, 

 like sensible little men, take in food-tubes and digging tools, and shut 

 their shells for rest. 



The coast fishermen here call these mollusks pompano-shells, because, 

 they say, they form the only food of that fish. The pompano has the 

 reputation of being the very finest fish for the table that swims in south- 

 ern waters; and if this splendid reputation is well deserved, and is due 

 to his living upon our little mollusks, surely the donax is worth all the 

 admiration we have given it. 



