330 ESSAY ON CLASSIFICATION. 



Cuvier, admitting, of course, the rectifications among the 

 groups of secondary rank, rendered necessary by the 

 progress of science, to which he has himself so largely 

 contributed. 



As to the classes adopted by Milne-Edwards, I have 

 little to add to what I have already stated before with 

 reference to other classifications. Though no longer 

 overruling the idea of plan, that of complication of 

 structure has still too much influence with Milne-Edwards, 

 inasmuch as it leads him to consider as classes, groups of 

 animals which differ only in degree, and are therefore 

 only orders. Such are, no doubt, his classes of Mollus- 

 coids and those of Worms, besides the Myriapods and 

 Arachnids. Respecting the Fishes, I refer to my re- 

 marks in the first section (p. 298) of this Chapter. 



CLASSIFICATION OF MILNE-EDWARDS. 



The following diagram is drawn from the author's " Cours elemeutaire 

 d'Histoire naturelle"; Paris, 1855, 1 vol. 12ino., 7th edit.; in which he has 

 presented the results of his latest investigations upon the classification of 

 the Vertebrata and Articulata; the minor sub-divisions of the Worms, Mol- 

 lusks, and Zoophytes, however, are not considered in this work. 1 



I. OSTEOZOARIA, OR VERTEBRATA. 



Sub-branch. Allantoidians. Sub-branch. Anallanto- 



idians. 



CL. MAMMALIA. 1. Monodelphya. a. Pro- 

 pria. Ord. Bhnana, Quadruniana, Cheiroptera, 



Insectivora, Rodentia, Edentata, Carnivora, Am- rennibranchiaj 



phibia, Pachyderniata, Rumiuantia. b. Piscifor- 

 inia. Ord. Cetacea. 2. Didelphya. Ord. Mar- 

 supialia, Monotremata. 



CL. BIRDS. Ord. Rapaces, Passeres, Scanso- 

 res, Gallinaj, Grallte, and Palmipedes. 



CL. REPTILES. Ord. Chelonia, Sauria, Ophi- 

 dia. 



CLASS BATRACHIANS. 

 Ord. Anura, Urodela, Pe- 



CL. FISHES. 1. Os- 

 sei. Ord. Acanthoptery- 

 gii, Abdominales, Sub- 

 brachii, Apodes, Lopho- 

 branchii, and Plectogna- 

 thi. 2. Chondropterygii. 

 Ord. Sturiones, Selachii, 

 and Cyclostomi. 



1 Consult, for these, his recent papers upon Polyps, Mollusks, and Crus- 

 tacea, iu the Ann. des Sc. Nat. 



