72 PETROMYZON. 



The manner in which the gills are arranged, un- 

 der the skin, is a subject of deep interest to the 

 anatomist, inasmuch as he discovers at once, a 

 structure of the utmost consequence to the species, 

 since they were expressly designed by nature to 

 occupy a place where no other beings were loca- 

 ted, viz : — the muddy beds of bays, — the ooze 

 which accumulates in estuaries, and in fact, just 

 those places where fishes could not live on account 

 of the foreign matter in the water, which would 

 clog up their gills, and consequently produce 

 death. 



Between the side of the mouth and the skin, 

 there is a long canal, or pocket, in which the bran- 

 chiae, or fringes of the gills are placed in a row. 

 Opposite the space or little apartment, between 

 every two fringes, there is a round hole, tipped with 

 a cartilaginous ring, precisely like a hoop, to keep 

 it always open. When the lamprey is snugly coil- 

 ed up in a bed of loose, dark mud, where it finds 

 a variety of marine worms, putrid remains of vari- 

 ous animals, he, forced into such basins by the 

 eddying tides, it strains the water through a very 

 small aperture, into which it forms its mouth, till the 

 under side, or gular pouch is considerably distend- 

 ed, when by the action of the muscles about the 

 jaws, it is driven through all the fringes, and comes 

 out at the orifices. By this beautiful, yet simple 



