310 



ANIMALS. [Ch. XXXVI. 



gardener produces lijbrid races, it seems strange that we do 

 not oftener meet with hybrids in a state of nature. But it 

 must be remembered that the conditions in the two cases are 

 very different. 



The stigma imbibes, slowly and reluctantly, the granules 

 of the pollen of another species, even when it is abundantly 

 covered with it ; and if it happen that, during this period 

 ever so slight a quantity of the anther-dust of its own species 

 alight upon it, this is instantly absorbed, and the effect of the 

 foreign pollen destroyed. Besides, it does not often happen 

 that the male and female o 

 species, arrive at a state c 



5 



matui 



time. Even where such synchronism does prevail, so that a 

 cross impregnation is effected, the chances are very numerous 



'» 



hment 



The greater part even of those seeds of wild plants which 

 are well ripened are either eaten by insects, birds, and other 

 animals, or decay for want of room and opportunity to ger- 

 minate. Unhealthy plants are the first which are cut off by 

 causes prejudicial to the species, being usually stifled by more 

 vigorous individuals of their own kind. If, therefore, the re- 

 lative fecundity or hardiness of hybrids be in the least degree 



inferior, they cannot maintain their footing for many gener- 

 ations in a wild state. In the universal struggle for existence, 

 the right of the strongest must eventually prevail ; and the 

 strength and durability of a race depends in a great degree 



on its prolificness, in which hybrids are acknowledged to be 

 generally deficient. 



It is admitted on all hands, that in proportion as the species 

 of animals and plants are remote from each other in structure 

 they are averse to sexual union ; and that species which the 

 zoologist and botanist would usually class as distinct, most 



'y refuse to unite, and if they can be crossed and 

 produce new offspring, the hybrids are sterile. Whenever we 

 find that two races regarded by many as true species will 

 produce fertile hybrids, we are reduced to the dilemma of 

 choosing between two alternatives ; either to reject the test 

 of hybridity, or to declare that the two species, from the 



union of which the fruitful T3roo-env hns su^rmio-. wpvp uifire 



common 



/ 



I 





V 





\ 



S^ 



\ 



c 



/ 



CU' 



t 





eci 



lific 



atel) 

 ete 



1 



the 

 faroi 



CO 



arep 



(p. 31 

 Te 



apar 

 jack; 



pose 



of 01 



kee] 

 aboi 

 kepi 

 and 

 Iiidi 



prod 



state 

 bee 



Yeti 

 not} 

 plain 

 Buite 

 ^liic: 



111 



tiler 



ton>^| 



11 



1] 



( 



•iisti 

 a f^ 



sliiix 



