THE DOUBLE STOCK, ITS HISTORY AND BEHAVIOUR. 461 



It has been suggested by Oberdieck * that this view arose after 

 the introduction of the new, large-flowered English Summer Stocks, 

 which had larger and more beautiful flowers than the familiar so-called 

 German stocks with shorter pods and more numerous seeds, the seeds 

 of the latter sort being so crowded as to be often compressed by one 

 another. However this may be as regards the origin of a view some- 

 what widely held, we do not find that the view itself is borne out by 

 the facts. Experiments have shown that, among double-throwing 

 single strains, some with particularly long pods in which practically 

 every seed is regular and flat give as high a proportion of doubles as 

 those with short pods and many small, irregular seeds. And, conversely, 

 some strains may have these short pods and irregular seeds and yet 

 give no doubles at all. Further, if the flat seeds be sorted from the 

 irregular ones in the same pods, an equal proportion of doubles will, on 

 the average, be obtained from both samples, f The irregular shape 

 of the seeds is undoubtedly the result of pressure during development 

 and the ultimate form of the seed has nothing to do with the singleness 

 or doubleness 01 the flower which it produces. This flower character, 

 like any other, is, as we now know, determined at the moment of 

 fertihzation (see later, p. 466). 



6. The selection for sowing of old seed rather than fresh. 

 Advocated by Thiele,| Bosse,§ and Chate,|| and mentioned 

 as a common belief by Oberdieck.^ This idea seems to have 

 been held in regard to other plants besides Stocks. (See BossE ** 

 and Fairweather It concerning Balsams.) As the result of 

 experiments on this point Bosse came to the conclusion that 

 two- or three - year - old Stock seed gave predominantly doubles, 

 current year seed more singles, and that the same was the case with 

 Balsams. He sowed one-year-old and six-year-old Stock seeds in 

 the same bed, and states that the former developed more quickly and 

 gave almost entirely singles ; the latter produced only ten among several 

 hundreds of doubles. Chate was of the same opinion. Writing of 

 Stocks, he says that " experience has proved that seeds two years 

 old give more doubles than those one year old." Fairweather's 

 statement in regard to Balsams is to the same effect. He writes : 

 " The seed of Balsams should not be less than three or four years 

 old when sown ; the best double flowers which I have procured this 



* Wiener Illustririe Garten-Zeitung, 1879, p. 307. 



t See Saunders, " Further Experiments on the Inheritance of ' Doubleness 

 and other Characters in Stocks," Journal oj Genetics, vol. i. 191 1, p. 366. 

 Also " Double Flowers," Jour. oJ the Roy. Hort. Sac. vol. xxxviii, 1913, p. 480, 

 where figures are given showing the different form of the seeds in short and 

 long pods respectively. 



% See Goebel, loc. cit. 



§ Verhandl. d. Preuss. Gartenhau-Vereins, iv. 1828, p. 276; quoted by 

 Bronn in Handbuch der Geschichte der Natur, ii. p. 77. 

 II loc. cit. p. 73, 

 ^ loc. cit. 

 ** loc. cit. p. 77. 



ft Trans. Hort. Soc. vol. iii. p. 406. 



