108 CLASS REPTILIA. 



The Monitors, recently called, by a singular mis- 

 take, TUPINAMBIS,* 



Are that genus in which there are species of the 

 largest size. They have teeth in both jaws, but 

 want them in the palate. The greater number of 

 them may be recognized by their tail, laterally com- 

 pressed, which renders them aquatic. As in the 

 neighbourhood of waters they are sometimes near 

 the crocodiles and caymans, it is reported that they 

 advertise, by a hissing noise, the approach of those 

 dangerous reptiles. This assertion, in all proba- 

 bility, has given rise to the names of safe-guard and 

 monitor in some of the species. But this assertion 

 is any thing but certain. 



They are divided into two very distinct groups. 

 The first, or that of 



The Monitors, properly so called. 



May be known by small and numerous scales upon 

 the head and limbs, under the belly, and around the 

 tail, which last has a keel underneath, formed by a 

 double range of projecting scales. Their thighs are 

 destitute of the range of pores which we find in 

 many other Saurians. They all belong to the an- 



• Marcgrave, speaking of the safeguard of America, says that it is named 

 Teyu guacu, and, among the Topinambos, Temapara {Temapara Tupi- 

 nambis). Saba has taken this last word for the name of the animal, and all 

 other naturalists have copied him. 



