SMELL 45 



this imist be got rid of in some way because it does 

 not gi-ow as the true skin l)eneath does. In all above 

 the reptiles it is shed in little fragments, dropping off 

 all the time or going with some special bath. 



The true skin of the amphibians stays and en- 

 larges with the body, as in other vertebrates. It is 

 this that has in it the glands for secretions, the arteries 

 for breathing, and which lies above the lympli-cavi- 

 ties, etc. — a great and important organ in every verte- 

 brate. 



Smell 



Amphibians are better endowed for smelling than 

 are the lishes. 



In the tadpoles the nostrils are mere depressions 

 in the snout, not connected Avith the mouth, and they 

 are tlien like those of most fishes. But in adult 

 forms the nostrils open into the mouth, whereby the 

 creature both breathes and smells by the air. The 

 positions of these openings differ in the frog-forms 

 and in the tailed forms. They differ in separate spe- 

 cies of each group also, and are sometimes used in 

 classification or description. There is much in the 

 arrangement of the mucous membrane of the frog's 

 nose which implies that it smells well. If the strong 

 odors from the glands of the neck are used as charm- 

 ing perfumes (they are more likely for defense or de- 

 fiance) this would hint that there must be fairly good 

 smelling powers. But it does not take much nose to 

 smell some odors — especially that of garlic, which the 

 excretion of the toad resembles. 



