

' 



! 



236 SELECTION. CHAP-XXI 



< 



accidental that the great majority of the culinary and agricul- 

 tural plants which have yielded numerous races are annuals or 

 biennials, which therefore are capable of rapid propagation and 

 thus of improvement. Sea-kale, asparagus; common and Jeru- 

 salem artichokes, potatoes, and onions, alone are perennials 

 Onions are propagated like annuals, and of the other plants 

 just specified, none, with the exception of the potato have 



yielded moi 



No doubt fruit 



which cannot be propagated quickly by seed, have yielded a 

 host of varieties, though not permanent races; but-these, judging 

 from pre-historic remains, were produced at a later and more 

 civilised epoch than the races of culinary and agricultural plants. 

 A species may be highly variable, but distinct races will not 

 be formed, if from any cause selection be not applied. The 

 carp is highly variable, but it would be extremely difficult to 

 select slight variations in fishes whilst living in their natural state, 

 and distinct races have not been formed ; 46 on the other hand, a 

 closely allied species, the gold-fish from being reared in glass 

 or open vessels, and from having been carefully . attended to by 

 the Chinese, has yielded many races. Neither the bee, which 

 has been semi-domesticated from an extremely remote period 

 nor the cochineal insect, which was cultivated by the aboriginal 

 Mexicans, has yielded races ; and it would be impossible to 

 match the queen-bee with any particular drone, and most difficult 

 to match cochineal insects. Silk-moths, on the other hand, have 

 been subjected to rigorous selection, and have produced a host 

 oi races. Cats, which from their nocturnal habits cannot be 

 selected for breeding, do not, as formerly remarked, yield dis- 

 tinct races m the same country. The ass in England varies 

 much in colour and size ; but it is an animal of little value, 

 bred by poor people ; consequently there has been no selection, 

 and distinct races have not been formed. We must not attribute 

 the inferiority of our asses to climate, for in India they are of 

 even smaller size than in Europe. But when selection is brought 

 to bear on the ass, all is changed. Near Cordova, as I am in- 

 formed (Feb. 1860) by Mr. W. E. Webb, C.E., they are care- 

 fully bred, as much as 200Z. having been paid for a stallion ass, 



^Isidore Geoffrey St. Hilaire, <Hi s t. Nat. Gen.,' torn. iii. p. 49. On the 

 Cochineal Insect, p. 46. 



* 





t 







'. 



• 



v 



V 





f 



