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Class BATRACHIA. 



Cold-blooded Vertebrates usually breathing by gills during at 

 least part of their existence, undergoing metamorphoses*. In 

 the recent forms, body naked or with scales imbedded in the skin, 

 and skull with a lai-ge paraspheuoid, devoid of supraoccipital aud 

 basioccipital, and articulating with the vertebral column by two 

 condyles. Paired limbs as in the higher Vertebrates, pentadactyle 

 or derivable from the pentadactyle type. 



Represented in the Fauna here dealt with by two Orders •-- 



I. ECAUDATA, Frogs and Toads. 



II. APODA, Csecilians. 



Order ECAUDATA. 



Four limbs aud no tail. Radius and ulna and tibia and fibula 

 confluent; tarsus (astragalus and calcaueum) elongate, forming an 

 additional segment in the hind limb. Frontal bones confluent 

 with parietals, nasals with prsefrontals. 



The body is short, the dorsal vertebral column consisting of 

 but eight praesacral vertebrae (exceptionally still further reduced), 

 and the coccygeal vertebrae are confluent into a single styloid bone. 



* The young of certain species leave the egg or the body of their mother in 

 the perfect condition, thus dispensing with the metamorphosis. 



