CHAPTER XXXII 



THE ALLIES OF THE FROG: AMPHIBIA 



Blue dusk, that brings the dewy hours, 

 Brings thee, of graceless form in sooth 



Dark stumbler at the roots of flowers, 

 Flaccid, inert, uncouth. 



Edgar Fawcett, A Toad 



Definition of Amphibia (Gr. amphibios, "capable of living 

 in both air and water")- The frog belongs to the class 

 Amphib'ia, to which belong also the toads, newts, and 

 salamanders. Amphibians are cold-blooded vertebrates 

 covered with a smooth or rough, moist skin, in which are 

 numerous mucous glands. In the immature state most am- 

 phibians are adapted to a life in the water and breathe 

 by gills ; when adult the gills are in the majority of cases 

 absorbed, and the animals breathe by lungs. Four limbs 

 are usually present. Nearly all amphibians lay eggs, from 

 which the young develop. 



Two out of the three orders into which the class is divided 

 will be discussed here. One of these orders includes the sal- 

 amanders and newts, the other the toads and frogs. 



Salamanders and Newts. The Urode'la (Gr. oura, "tail"; de- 

 los, "conspicuous") are elongate forms, with a tail through- 

 out their lives. They are often, but erroneously, called lizards, 

 and resemble the latter only in external form. The eggs are 

 laid usually in the water in strings, or in large masses re- 

 sembling frogs' eggs, or singly, attached to the leaves of 

 water plants. 



The red-backed salamander (Pleth'odon cine' reus) and a 

 number of other species spend their entire life in moist 



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