98 KAMBLES OF A NATURALIST. 



modified for flying or for swimming ; they are deri- 

 vatives of the great types of the Mammalia. It will 

 be readily understood that there is no fixed limit to 

 the number of these derivatives, and that every 

 primitive type may engender several, whose diver- 

 gences will vary in accordance with the intensity 

 and diversity of the modifications from which they 

 have originated. 



At this point of our inquiries, the entire mass of 

 beings which we have been studying will appear to 

 us to be decomposed into a somewhat limited number 

 of primitive types, around which their immediate 

 derivative types are disposed at various distances, 

 and in accordance with a certain order. These are 

 in their turn surrounded by secondary derivatives, 

 and so on in a consecutive series. Existing species 

 may all be classified within this theoretical animal 

 kingdom, being distributed in accordance with the 

 degree of resemblance which they present to their 

 ideal types. It is thus that the celestial bodies, 

 grouped together in a thousand different ways, 

 gravitate around one another, with their planetary 

 attendants circling round them either isolated or 

 accompanied by satellites. On our earth, no less 

 than in celestial space, we find that nature faithfully 

 adheres to those wondrous laws of analogy which she 

 observes in all her grander manifestations, and thus 

 we behold on the surface of our globe the same 

 spectacle of unity and harmony which, in the im- 

 mensity of space, strikes the senses with the pro- 

 foundest impressions of wonder and admiration. 

 The absolute ideal type of the animal has never 



