128 MERISTIC VARIATION. [part i. 



4. The frequency of substantial if imperfect bilateral sym- 



metry in the variations, but the occasional occurrence 

 of asymmetry also. 



5. The special variability of some types, e.g. Simia satyrus ; 



the Bradypodida? ; Bombinator igneus. 



6. The evidence that this variability may occur without 



the influence of civilization or domestication. 



II. As regards principle. 



1. The occasional, though not universal, association of for- 



ward Homceosis with increase in number and of back- 

 ward Homoeosis with reduction in number. 



2. The frequent correlation between Variation in several 



regions, such correlated Variation being sometimes 

 unilateral. 



3. The impossibility of applying a scheme of Homology 



between individual segments. 



