HYBRIT30US ANIMALS. 429 



duals of a particular species are drawn together by mutual 

 sympathy, and excited to action by a common propen- 

 sity. The produce of a conjunction between individuals 

 of the same species, partakes of the characters common to 

 the species, and exhibits in due time the characteristic 

 marks of puberty and fertility. In a natural state, the se- 

 lective attribute of the procreative instinct unerringly guides 

 the individuals of a species towards each other, and a pre- 

 ventive aversion, turns them with disgust from those of an- 

 other kind. 



In a domesticated state, where numerous instincts are 

 suppressed, and where others are fostered to excess, indivi- 

 duals belonging to different species are sometimes known 

 to lay aside their natural aversion, and unite in the busi- 

 ness of propagation. Instances of this kind occur among 

 quadrupeds, birds and fishes, among viviparous and ovi- 

 parous animals, where impregnation takes place within 

 as well as when it is effected without the body. The pro- 

 duct of such an unnatural union is termed a Hybridous 

 animal. The following circumstances appear to be con- 

 nected with hybridous productions. 



1. The parents must belong to the same natural genus 

 or family. There are no exceptions to this law. Where 

 the species differ greatly in manners and structure, no con- 

 straint or habits of domestication will force the unnatural 

 union. On the other hand, sexual union sometimes takes 



young plants, are prepared in the absence of sexual organs, and, consequent- 

 ly, without impregnation. Upon falling off from the parent, they strike 

 root and enjoy an individuality of character, as decided as if the reproduc- 

 tive organs had gone through the whole of the ordinary process. By means 

 of such extensions, and without ever producing seeds, the Festuca vivipara 

 is found in every pasture field of the northern islands of Scotland. When 

 extensions are obtained from healthy parents, or generated by such, their 

 duration will probably extend to the ordinary term assigned to the species. 



