102 THE OCEAN. 
pable of improvement, each filling its own peculiar 
place in its own circle, which the others could not 
fill. 
Tue SHRIMPER. 
The Shrimp and Prawn, like the Lobster, have the 
extremity of the body furnished with broad overlap- 
ping plates, strongly fringed, which, expanding in 
the shape of a fan, constitute a powerful fin. The 
body, a little behind the middle, has a remarkable 
bend downwards, though it may be brought nearly 
straight. Their motion when swimming is very 
swift, and in a backward direction, and is performed 
by striking the water forcibly with the tail-fin, the 
