The Lamarckiana-Faniily. 221 



in the middle of the field. Lastly, in the autumn of 1887 

 I collected the seeds of O. lacvifolia. I obtained in this 

 way three groups which, in conformity with the prin- 

 ciple of nomenclature adopted by growers of beets, I call 

 families ; and these I continue to grow, separately, to the 

 present day. 



From these three families and their numerous lateral 

 branches I have derived my wdiole culture, which has em- 

 braced several thousands of individuals almost every 

 year. Latterly several hundreds of plants have been arti- 

 ficially fertilized for seed purposes every year. 



Furthermore I have imported O. hrcvistylis direct 

 from Hilversum, because it did not arise in mv cultures. 

 I have also occasionally made collections of seed in the 

 field to afi^ord material for control experiments. 



In each of these three families new species have arisen 

 in my garden ; and they have been essentially the same in 

 the three groups. I shall deal with them separately : first 

 with that derived from the rosettes, the progeny of which 

 I shall call the LamarckiafiaA^xmXy. Of this family the 

 main trunk (§2) and a lateral branch (§5) wnll be dealt 

 with separately, for the sake of simplicity of treatment ; 

 but the results arrived at with the latter agree, in their 

 broad features, with those obtained from the former. 



From the seeds of O. lacvifolia the Lacvifolia-imn'iW 

 (§6) arose; from the seeds of the above-mentioned fruit 

 a group wdiich I shall call the La/a- family. 



§ 2. THE LAMARCKIANA-FAMILY. 



The original parents of this family were, as we have 

 already seen, moved to the botanical garden in Amster- 

 dam in the autumn of 1886. They flowered in 1887, 



