170 Observation of the Origin of Juirieties. 



doubt tliat the wild form exists in the mixtures grown 

 in botanical gardens. But in order to strengthen this 

 proof I have cultivated the isolated race for one more 

 generation. For this purpose I selected three vigorous 

 plants from amongst the 1893 crop whose terminal in- 

 florescences had 12 ray-florets, and left them to be fer- 

 tilized by themselves and by their like after all plants 

 with 13 or more rays had been eradicated. From these 

 three seed-parents I harvested the seed separately and 

 raised three families, in 1894, on different beds. The 

 rays of the terminal inflorescences were recorded, and the 

 experiment brought to an end. 



I shall now give the results of these three counts 

 made in 1894 together with that of 1893. It will be 

 seen that the series of figures correspond with one an- 

 other exactly ; at any rate as nearly as is necessary for 

 the object of this experiment. The composition of the 

 four cultures in the two generations was as much the 

 same as we should expect four samples of an ordinary 

 species to be. 



THE 13-RAYED RACE. 



VARIATION IN NUMBER OF RAYS^ IN TWO GENERATIONS. 



Ray-florets 8 9 10 11 12 13 14 15 16 17 18] 19 20 21 



1893 210 7 13 94 25 7712030 



1894. First family 1 10 59 18 2 3 4 1 2 1 



" Second" 00 14 1189 115002 100 



" Third " 01 2 3 10 73 21 1200000 



Total, 1894 1 3 8 31 221 50 8 5 4 3 1 2 1 



The total for 1894 is given in the form of a curve 

 in Fig. 31 A. The whole number of individuals dealt 

 with in this year was 338.^ 



In order to isolate the 21 -rayed race out of the same 



^ For a detailed comparison of the curves of the two years see 

 Archil' fiir Entwickelungsmech., II, 1895, loc. cit., p. 62. 



