ZOOLOGY 



SECTION XIII 



PHYLUM CHORDATA. 



In the arrangement which it has been found convenient 

 to follow in the present work, the Vertebrate animals (Fishes, 

 Amphibians, Reptiles, Birds, and Mammals), together with the 

 Cephalochorda or Lancelets, the Urochorda or Ascidians, and 

 the Hemichorda or Balanoglossiis and its allies, are all grouped 

 together in a single phylum — the Chordata. The main groups 

 comprised in this assemblage, however, differ so widely from 

 one another in certain essential points, and the common features 

 unitinjQj them together are so few, that it has been, thontrhh 



(y 



-^ 



ERRATA. 



PAGE. 



9, description of Fig. 710, /or "Fig. 667 '" rtwl " Fig. 709.'^ 

 17, line 8 from bottom, /or " enrV read " (end)". 

 19, line I, /or " peribranchial " read " peripharyngeal." 

 183, Fig. 840, /or " Pristurus " read " Pristiurus." 

 229, description of Fig. 88.5, for " dorsa "" read •' dorsal." 

 322, line 20 from top, /or " innominiafa" read " iimominata." 

 432! lines 3 and 20 from top, for " Apertyx '■' read " .\pteryx.'^ 

 .500, line L/or " Arycteropus " read '■ Orycteropus.'' 

 606, line 9 from top, /or " Squolodon/.idoe'' read '' SqiuilodoiUida>.'' 

 620, line 3 from bottom, for " import " read " important." 



