The Choice of Seeds in Selection. 337 



biennial individuals from the upper and hjwer fruits of 

 the same spike. In Viola tricolor maxima the small sum- 

 mer iiowers furnish the main quantity of seed. It never 

 occurs to a seed collector to regard them as of less value 

 than the first seeds. In many double plants, especially 

 in Begonia, it is practically only the flowers which bloom 

 last that produce pollen and set seed. This seed is always 

 sown without any detrimental result to the degree of 

 doubling of the variety. 



On the other hand it is generally regarded as desirable 

 to harvest the lower seeds of the inflorescence in the cox- 

 comb, Celosia cristata ; and in the case of the crested spe- 

 cies of ferns {Varictates cristatae) the spores which are 

 found on the dissected leaves, and still more on the tips 

 of such leaves, are regarded as the best, although spores 

 found on the other parts of the leaves will certainly re- 

 peat the anomaly.^ Another instance which has been 

 studied by many investigators is furnished by the stocks, 

 whose double varieties have been known for a very long 

 time, for a century at least, to consist in each generation, 

 of double and single plants in about equal numl^ers.- 

 Tbe former are absolutely sterile, lacking pistils and 

 pollen as a result of their petalomania (see Vol. I, p. 

 194), so that only the latter can play a part in the con- 

 tinuation of the race. There are certain differences be- 

 tween the seeds which produce the single and the double 

 specimens. The latter are heavier and germinate more 

 quickly,^ and the young plants can be sorted out in the 



^ See the long list of references given by Goebel, Organo^raf^hic, 

 I, p. 158; Verlot, loc. cit., p. 97; Carkiere, loc. cit., p. 67; Kencelv 

 Rridgmann, Ann. Sc. nat., 4 Seric. Vol. XVI, p. 367; C. T. Druerv. 

 Jonin. Roy. Hart. Soc, Vol. XII, III, 1890, p. 517, etc. 



" E. Chate Fils, Culture pratique des giroHees, Paris, Biblioth. 

 de I'horticulteur praticien. 



^NoBBE, Botan. Centralhlatt, Vol. XXXII, 1887, p. 253. 



