CROSSING AND CLOSE-INTERBREEDING. 215 



parts. Where, then, some of the parts are not present, 

 the reproductive capacity is impaired; and, if there be 

 a certain number of characters wanting, absolute ster- 

 ility sets in. Harmonious playjind movement of all 

 the parts, as in a mechanism, is requisite. There 

 must, as a sine qua non of physiological integrity, or of 

 normal coordination, be perfect exactness, — the closest 

 fitting in of each part. " All must full or not coherent 

 be," And all must rise (i. e., revert), in due degree. If 

 " Tis but a part we see, and not the whole," the 

 organism is thrown out of gear (to use a Yankeeismj. 



An individual, of any species, can exist in a per- 

 fectly healthy, normal state, only as a whole ; — that 

 whole, which comprises all the positive features of its 

 species; and, it is a fundamental and egregious error, 

 to suppose that, — as with pigeons and fowls, under 

 domestication, — the characters of the respective spe- 

 cies may be divided among many different varieties, 

 consistently with physiological perfection. It is an 

 error, also, to suppose, that the characters which, in 

 the well-bred (?) pig, are reduced or suppressed, may 

 be so reduced or suppressed, without evil being en- 

 tailed. It is an error, also, to suppose that the true 

 ratio of the development of the characters, respec- 

 tively, of the horse, sheep, and cattle, may be varied 

 in the individuals of those species, without detriment 

 to their fertility and constitutional vigor. 



Either, immediately, as with fancy pigeons, with 

 fancy fowls, and with highly cultivated pigs; ot, in 

 course of time, as with well-bred horses, cattle, and 

 sheep, — dependent, always, upon the degree of dis- 



