SUMMARY OF PROOFS. 353 
anatomy and the history of development, the harmonious 
agreement between the laws of the gradual development, 
the progressive differentiation and perfecting, as they 
may be seen in comparative anatomy on the one hand, in 
ontogeny and paleontology on the other. 
(6.) Dysteleology, or the theory of purposelessness, the 
name I have given to the science of rudimentary organs, of 
suppressed and degenerated, aimless and inactive, parts of 
the body; one of the most important and most interesting 
branches of comparative anatomy, which, when rightly 
estimated, is alone sufficient to refute the fundamental error 
of the teleological and dualistic conception of Nature, and 
to serve as the foundation of the mechanical and monistic 
conception of the universe. 
(7.) The natural system of organisms, the natural group- 
ing of all the different forms of Animals, Plants, and Protista 
into numerous smaller or larger groups, arranged beside and 
above one another; the kindred connection of species, 
genera, families, orders, classes, tribes, etc., more especially, 
however, the arboriform branching character of the natural 
system, which is the spontaneous result of a natural arrange- 
ment and classification of all these graduated groups or 
categories. The result attained in attempting to exhibit 
the relationships of the mere forms of organisms by a 
tabular classification is only explicable when regarded as 
the expression of their actual blood relationship ; the tree 
shape of the natural system can only be understood as the 
actual pedigree of the organisms. 
(8.) Lhe chorology of organisms, the science of the local 
distribution of organic species, of their geographical and 
topographical dispersion over the surface of the earth, over 
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