— 376 — 



on the other side of the road: all the plants were as fig. 5 a: 

 grandifoliata, non atropurpurea, erecta and non caespitosa (Table 

 I, population Y, page 379). Apparently the characters of the 

 type from the dunes were favourable to the plants under 

 the conditions of life there. One might presume that the 

 diverging appearance of this afore-mentioned type was a 

 modification induced by the external conditions. The most 

 exact method to prove whether the extreme characters were 

 phenotypically or genotypically induced would have been to 

 take the plants from these populations and propagate them 

 in clons under identical conditions in order to see if they 

 became identical. I did not do so, but instead of that I collected 

 seeds from the two types and these were sown under identical 

 conditions in the Botanical Garden, Copenhagen. They bred 

 true to type: all plants of seeds from the dune became parvi- 

 foliata, atropurpurea and all plants of seeds from the field 

 became grandi] oliata, non atropurpurea, the offspring being 

 just as different as the mothertypes in fig. 5 a and b. By 

 this it was proved that the extreme characters were hereditary 

 and not induced by the conditions. 



All the above mentioned characters I have tried under 

 cultivation, and they proved to be genotypically conditioned. 

 Sometimes a segregation was noticed: some of the prostrata 

 plants taken in nature are homozygotic and some are hetero- 

 zygotic, and therefore seeds of them show segregation in 

 erecta and prostrata. — Seeds of an albino tic tricolor gave 

 many albinotic and a few violet plants ; (alba is recessive, and 

 the violet plants were from seeds pollinated with pollen from 

 violet flowering plants). — The first plant cultivated with 

 the character emarginata (lateral sepals) was homozygotic 

 and gave by self-fertilization only emarginata individuals. 



On the whole, most of the types collected in nature show 

 no segregation except in such characters as the flower-colours 

 lutea and violacew (tricolor) and in the characters maculata 

 and non maculata (the style); likely they are homozygous 

 in most characters. The probable cause to this phenomenon 

 will be discussed later. 

 3. By researches in Genetics. The different characters 

 have been crossed in order to determine the factors and the 

 limit of the characters against each other. It will still take 



