216 HEREDITY AND ENVIRONMENT 



new and unexpected characters sometimes de- 

 velop in the offspring, which were not present, 

 so far as known, in any of the ascendants, but 

 which, after they have once appeared, are 

 passed on by heredity to descendants. Such 

 inherited variations are usually of two kinds, 

 continuous or slight, and discontinuous or 

 sudden variations. The latter are especially 

 noticeable when variations occur in the normal 

 number of parts, as in four-leaved clover, or 

 six-fingered men, and such numerical varia- 

 tions have been called by Bateson "meristic." 

 However, sudden variations may include any 

 marked departure from the normal type, in 

 color, shape, size, chemical compositions, etc. 

 Such sudden variations have long been known 

 to breeders as "sports," and both Darwin and 

 Galton pointed out the fact that such sports 

 have sometimes given rise to new races or 

 breeds, though Darwin was not inclined to 

 assign much importance to them in the gen- 

 eral process of evolution. Galton, on the other 

 hand, maintained that variations, or what 

 would now be called "continuous variations," 

 cannot be of much significance in the process 



