106 BRANCH VERTEBRATA. 





 ORDER MONOPNEUMONIA (mon o nu mo'ni a). 



The Australian Ceratodus (se rat'o dus) sometimes 

 reaches a length of six feet, and is known habitually to 



FIG. 181. 



Ce rat' o dus fors' ter i. Barramunda. 



leave the water and crawl about on land. It is prized 

 by the natives for its flesh. 



CLASS BATRACHIA (ba tra'ki a). 



We meet here with a most interesting class of verte- 

 brates, the typical members of which in early life bear 

 a strong resemblance to the fishes, though later on they 

 change their character, losing their tails and having 

 lungs take the place of gills. The animals now become 

 terrestrial, but require moisture, as the naked skin, being 

 well supplied with blood-vessels, is an important factor 

 in blood purifying. The eggs, like those of fishes, are 

 without a protecting shell, being generally deposited in 

 the water. The BATRACHIA, as well as some of the pre- 

 vious forms, have the power of restoring lost parts, as 

 the tail, or limbs. All are harmless to man. 



ORDER URODELA (u ro de'la) 



To this order belong those Batrachians that have an 

 elongated body, moist skin, and persistent tail, and usually 



