170 On the Classification of Mammalia. 



an insectivorous stem {Edentata proper), and a carnivorous 

 stem (Mo)totremata.) The carnivorism in the trunk of Eden- 

 tata is of the lowest grade, and subordinated ; as the carni- 

 vorous propensities only attack invertebrates, that is to say, 

 animals of a much inferior rank, comparatively very weak 

 and defenceless. 



Above Monotremata we place Cetacea (whales and dol- 

 phins) ; Edentata proper, above the Insectivora ; and above 

 Tardigrada, the Sirenidia, or so-called herbivorous cetaceans, 

 the Pachydermata and Ruminantia. 



The trunk of Marsupialia exhibits likewise three stems, 

 an herbivorous, an insectivorous and a carnivorous. Above 

 which we have, the Rodentia, containing the herbivorous 

 stem ; the Insectivora, continuing the insectivorous stem in 

 common with Edentata proper ; and Carnivora, continuing 

 the carnivorous stem. 



Thus above Edentata and Marsupialia, we have, on an- 

 other level, Cetacea, Sirenidia and Walrus, Pachydermata, 

 Ruminantia, Rodentia, Insectivora, and Carnivora ; that is to 

 say, all the normal types which represent the full develop- 

 ment of the class as synthetically combined in Edentata and 

 Marsupialia below. 



The fact that Insectivora are foreshadowed both by Eden- 

 tata and Marsupialia, shews that there exists a close con- 

 nection between the two trunks of the class. The insecti- 

 vorism is intermediate in rank between herbivorism and car- 

 nivorism ; it is of a higher grade than the former, and of a 

 lower than the latter. The predominating feature of the 

 trunk of Edentata consists in the vegetable diet, and in the 

 want of a complete set of teeth ; the predominating feature 

 of the trunk of Marsupialia, on the contrary, consists in the 

 animal diet, and the possession of a complete set of teeth. 

 Accordingly there can be no doubt that Edentata are lower 

 in grade than Marsupialia : they are the lowest grade in 

 their class. 



It will be obvious, also, that here Edentata rank the 

 lowest in grade amongst the normal groups of the class ; 

 still shewing that Edentata are inferior to Marsupialia, the 

 latter foreshadowing groups of a marked superiority. 



