THE EVOLUTION OF TYPES 271 



animals except the Rasse are little known though the Bintu- 

 rong differs from the others in being more thoroughly omniv- 

 orous, even including fruit in its dietary. The differences in 

 palate and in tooth form are very striking. The Easse and the 

 African Civet are long jawed; the other two, in each of which 

 the first premolar is shed in early life, are short jawed. The 

 insectivorous character of the teeth of the Rasse is indicated 

 by their sharp cusps; the carnivorous tendency by the carnas- 

 sial form of ^r. The carnassial development is greatest in 

 the Fossa, the jaws and teeth of which closely resemble those of 

 the Cats. In the African Civet on the other hand the teeth 

 and jaws simulate those of the Dog. We shall not stay to dis- 

 cuss these resemblances in detail: they are sufficiently obvious 

 upon careful examination of the photographs and are approxi- 

 mate recapitulations in another family of the general method of 

 tooth differentiation found in the true Cats and true Dogs. It 

 is perfectly plain also that the dentition of the Binturong orig- 

 inated from a Rasse-like form, now considerably modified: the 

 crowns are small and the cusps greatly reduced, a typical retro- 

 grade character which may be seen also in the dentition of the 

 Kinkajou (Fig. 100). 



The other example chosen (Fig. 100) does not show diver- 

 gent modifications as have been noted in the feline- and canine- 

 like Viverridae just presented. It illustrates the evolution of 

 a single form of dentition, that of the Raccoon, showing as 

 nearly as possible the stages met with in ancestral fossil Rac- 

 coons, reproduced in existing and closely related animals. It 

 presents further the evolution of a retrogressive type, the 

 Kinkajou, comparable with the Binturong. Lastly it exempli- 

 fies a very strange development, the formation of a pure herbiv- 

 orous dentition from one originally carnivorous. This is all 

 the more impressive when we recall the fact that modern Arti- 

 odactyla are descended in all probability from carnivorous 

 forms, the Creodont family Mesonychidae. The simplest type 



