FOOD-GATHERING ORGANS. 191 



stiff hairs, projecting nearly at right angles to its 

 length ; these hairs meeting point to point those of the 

 next bristle, and so on in succession, there is formed a 

 most complete net of regular meshes, which must en- 

 close and capture every tiny insect or animalcule that 

 floats within its range ; while, at each out-cast, it opens 

 at every mesh, and allows all refuse to be washed away 

 or fall to the ground. Tor we are not to suppose that 

 the captures thus promiscuously made are as indiscri- 

 minately swallowed. A multitude of atoms are gathered, 

 which would be quite unfit for food ; and a power of 

 selection resides in the mouth, whether it be the sense 

 of taste or touch; or any. other analogous but recondite 

 perception, by which the useful only is admitted, the 

 worthless, or at least the injurious, being rejected. 



Companions of the Flat- crabs, closely allied to them 

 in all essentials of form and structure, yet widely sepa- 

 rated by general figure and appearance, and to some 

 extent by habits too, are the Squat-lobsters. They, too, 

 are somewhat flat, but they are more decidedly lobster- 

 like, with a distinctly jointed abdomen as broad as the 

 body, terminating in wide and strong swimming-plates. 

 This portion is, during rest, thrown-in under the body, 

 much more completely than a true lobster or prawn can 

 do it, and yet is by no means so permanently set in 

 that position as in the true crabs. The Flat- crabs and 



