The Lamarckiana-Family. 223 



each year. Fertilization was always artificial; the flow- 

 ers set plenty of seed when impregnated with their own 

 pollen. The visits of insects were precluded by the use 

 of prepared paper bags.^ The production of new species 

 has not in the least suffered from all these precautions. 



I shall now summarize the whole history of this fam- 

 ily in the form of a genealogical tree (p. 224), including 

 in it only the main line of descent and the individuals 

 which mutated directly from it. 



The table shows the eight generations in succession; 

 the first 1886-1887, consists of the nine plants collected 

 in the field at Hilversum; this and the two following 

 generations each occupy two years. I did not sow the 

 seeds which I harvested in 1891 till 1895 ; from that time 

 on, each generation occupies only a year. In the column 

 over which O. Lam. is written are given the approximate 

 numbers of individuals which were examined either as 

 seedlings or as grown plants, in each year. These num- 

 bers do not refer to the total number of seeds sown or 

 even to the number of seedlings that came up, but to 

 plants which were examined separately. 



The table also shows the number of plants which 

 mutated in each generation, so far as they could be rec- 

 ognized with certainty. It is probable that these numbers 

 are in many cases too small because I had not nearly 

 space enough to grow all the seedlings separately until 

 they had so far grown that their true character was a 

 matter of absolute certainty. They had as a rule to be 

 examined as seedlings and it is probable that m this way 

 many cases of mutation were overlooked. 



I have only recorded the more important mutations 



^''On the Use of Transparent Paper Bags for Artificial Fertili- 

 sation," in Hybrid Conference Report ; Journal Royal Horticultural 

 Society, Vol. XXIV, April 1900, p. 266. 



