Chap. XXVHL CONCLUDING EEMAEKS. 425 



said to be the same with the dog still imported from Thibet 

 into the same region. The true greyhound existed during the 

 Roman classical period. Coming down to a later period, we 

 have seen that, though most of the chief breeds of the pigeon 

 existed between two and three centuries ago, they have not 

 all retained exactly the same character to the present day ; 

 but this has occurred in certain cases in which no improve- 

 ment was desired, for instance, in the case of the Spot and 

 Indian ground-tumbler. 



De Candolle 12 has fully discussed the antiquity of various 

 races of plants ; he states that the black seeded poppy was 

 known in the time of Homer, the white-seeded sesamum by 

 the ancient Egyptians, and almonds with sweet and bitter 

 kernels by the Hebrews ; but it does not seem improbable 

 that some of these varieties may have been lost and reap- 

 peared. One variety of barley and apparently one of wheat, 

 both of which were cultivated at an immensely remote period 

 by the Lake-inhabitants of Switzerland, still exist. It is 

 said 13 that " specimens of a small variety of gourd which is 

 " still common in the market of Lima were exhumed from an 

 " ancient cemetery in Peru." De Candolle remarks that, in 

 the books and drawings of the sixteenth century, the principal 

 races of the cabbage, turnip, and gourd can be recognised : 

 this might have been expected at so late a period, but 

 whether any of these plants are absolutely identical with 

 our present sub-varieties is not certain. It is, however, said 

 that the Brussels sprout, a variety which in some places is 

 liable to degeneration, has remained genuine for more than 

 four centuries in the district where it is believed to have 

 originated. 14 



In accordance with the views maintained by me in this 

 work and elsewhere, not only the various domestic races, but 

 the most distinct genera and orders within the same great 

 class— for instance, mammals, birds, reptiles, and fishes — are 



12 'Geographic Botan.,' 1855, p. 14 'Journal of a Horticultural 

 989. Tour,' by a Deputation of the Cale« 



13 Pickering, ' Races of Man/ donian Hist. Soc, 1823, p. 293. 

 1850, p. 318. 



