PETROMYZON. 73 



contrivance, no mud can get into the fringes, or 

 if it does into the side holes, the next exertion of 

 the jaws, throws a stream of water to wash it out 

 again. So far as the gular pouch is concerned, in 

 the respiratory function, the lamprey bears consid- 

 erable analogy to the lizards. Breathing, with 

 those reptiles, is an entirely voluntary act : the 

 mouth is drawn full of air, through the nostrils, 

 and then, the under jaw being in action like a bel- 

 lows, forces it into the lungs. 



As an article of food, they have been much priz- 

 ed, but as we do not see them very frequently in 

 the stalls, it is conjectured they are scarce, or there 

 are not purchasers enough to compensate for the 

 trouble of collecting them. 



FRESH WATER LAMPREY. 



FRESH WATER LAMPREY. Petromyzon Flu- 

 matilis. There is scarcely a portion of New Eng- 

 land, even in the most elevated regions, in which 

 the river lamprey may not be found. The ety- 

 mology of the name petromyzon, is found in two 

 Greek words, signifying to suck a stone. 



Usually, its color is a dark olive on the back, 



