THE BATEACHIA OF NORTH AMERICA. 19 



chia. The latter two divisions be regards as subclasses, imder the 

 names Monopnoa and Dipnoa. The Dipnoa (Batracbia) are divided 

 into ITrodelaand Batracbia (=:Anura). The Urodebuutnru are divided 

 iiitoPeronnibraucbiata, Derotremata (Trematodera pt. ofDiimeril and 

 Bibron), and Myctodera (salamanders in general). 



Mcuckel pnblisbed in 18GG bis Generelle Morpbologie. He tben dis- 

 tiugnisbed tbe Batracbia not only as a class from tbe Reptilia, but 

 placed it in a separate group of tbe vertebrata, wbicb bo called tbe 

 Anamnia, from tbe absence of tbe amnion, along witb tbo fisbes. He 

 uses indiscriminately tbe names Batracbia and Ainpbibia for tbe class. 

 lie divides it into two primary divisions, tbe Pbractampbibia and Lis- 

 sampbibia, Tbe former are the extinct forms, together with tiie Caici- 

 lii(hB. Tbe Lissampbibia are divided into tbree divisions: Sozobran- 

 cbia (Perennibrancbs), Sozura (CJrodela), and Anura. 



Cope, in a "Syno[)sis of the Extinct Batracbia of Nortli America," 

 ISOS (Proceedings of the Ac.ulemy Philadelpbia), recognized tlie Batra- 

 cbia as a class distinct from t'ae Reptilin, and divided it into six orders, 

 as follows: Tracliystomata (Sirens), Prot.ida, Urodela, Gymnophidia 

 (the Coeciliida;), Stegocepbali (extinct forms), and linura. In a paper on 

 the Batracbia of the Permian Period of North America, ISSf (American 

 Naturalist), two orders were added, the Rhacbitomi and Embolomeri, 

 l»uth extinct. In the " Origin of the Fittest" (Philadelphia, 1886) still 

 another order is added to tbe Batracbia, tbe Gauocephala of Owen, and 

 tlic Gymuopbiona(Ooeciliidse)are united witb the Urodela, making' eight 

 oi'ders iu all. This system is adopted in the present work. In 1865, in 

 u paper on the Primary Divisions of the Batracbia Salientia (Natural 

 History Review) tbe Anura were divided into Aglossa, Bufoniformia, 

 Aicifera, and Raniformia. These divisions are here adopted, except- 

 ing tbe B n fan i form ia. 



Huxley, Anatomy of Vertebratcd Animals, 1871, divides the vertj- 

 brata into Icbthyopsida, Sauropsida, and Mammalia. Tbe Icbth^'opsida 

 coriespond to the Anamnia of Haeckel, plus tbe Leptocardii and Mar- 

 sipobrauchii. This division is divided into two classes, the Pisces and 

 Amphibia (Batracbia). Tbe Reptilia and Aves form tbe Sauropsida. 

 The Amphibia embrace, according to Huxley, four orders, viz: Uro- 

 dela, Labyrinthodonta, Gymnopbioua, and Batracbia or Anura. The 

 Urodela are divided into Proteida and Salamandrida, wbicb corre- 

 spond to tbe Trematodera and Atretodera of Dumeril and Bibron. 

 Professor Hnxley gave tbe first clear osteological definition of the class. 



Gegenhaiir, iu the Elements of Comparative Anatomy, 1872, follows the 

 system of Haeckel so far as regards the higher grou[)s of vertebrata. 

 Tbe Batracbia are called Ampbibia, and have the tbree divisions pro- 

 posed by Merrem, but under tbe names Urodela, Anura, and Gymno- 

 pbioua. 



In tbe preceding review uo attem]»t bas been made to present the 

 views of all naturalists wbo have written on tbe vertebrata, but I have 



