Polycephalic Poppies 393 



is to be considered therefore as an experimental 

 basis for such expectations. 



First of all comes the question how many in- 

 dividuals are to be grown in a given place. 

 When sowing plants for experimental purposes 

 it is always best to sow in rows, and to give as 

 few seeds to each row as possible, so as to in- 

 sure all necessary space to the young plants. 

 On the other hand the seeds do not all germi- 

 nate, and after sowing too thinly, gaps may ap- 

 pear in the rows. This would cause not only a 

 loss of space, but an inequality between the 

 plants in later life, as those nearest the gaps 

 would have more space and more light, and a 

 larger area for their roots than those growing 

 in the unbroken rows. Hence the necessity of 

 using large quantities of seed and of weeding 

 out a majority of young plants on the spots 

 where the greatest numbers germinate. 



Crowded cultures as a rule, will give weak 

 plants with thin stems, mostly unbranched and 

 bearing only small capsules. According to the 

 rule, these will produce imperfect crowns of sec- 

 ondary pistils. The result of any culture will 

 thus be dependent to a high degree on the num- 

 ber of individuals per square meter. I have 

 sown two similar and neighboring beds with 

 the thoroughly mixed seeds of parent-plants of 

 the same strain and culture, using as much 



