96 White. 



individuals with beautiful comb-like expansions were secured the second 

 year. Time of sowing, according to de Vries (1909 — 10), (M. T. 2, 

 p. 498) is also a factor in the production of fasciated individuals. In 

 Holland, sowings of Crepis in April and May gave 30 — 40 per cent 

 fasciations, sowings at the end of July 20 per cent, and those made in 

 September, none at all. The same results were obtained with Taraxacum 

 officinale. Apparently early sowing gives the plant time to make a 

 strong rosette before winter stops growth. Crowding, pruning, and 

 nutrition are important factors. Crowding is said to lessen the percentage 

 of fasciated individuals, and increase the atavists in a hereditary race. 

 Pruning diverts the sap rapidly into lateral branches, and this, according 

 to de Vries and Goebel, arouses the latent character to somatic 

 expression. Nutriment is very important as evidenced by the remarks 

 on crowding, selection of seeds, etc. For the reason that fasciated 

 branches are often somewhat weakened by growth expansion, de Vries 

 thinks atavistic (normal) branches may perhaps produce the best seed 

 for continuing the race. By the same method of reasoning, absence 

 of fasciated branches on a fasciated main stem, which is very common, 

 are explained. Briefly then, in order to favor the expression of such 

 characters as fasciation, even though the character is said to be strictly 

 hereditary in a race, it is necessary, according to de Vries, to take 

 into consideration, environment of seed parents, character of seed (weight, 

 plumpness, etc.), climatic conditions, time of sowing, crowding, pruning, 

 and other methods of diverting sap or increasing the food supply 

 abruptly, and nutriment (soil, water, fertilizer, etc.). 



Growing in sterile sand decreases, while richly manured soil 

 increases the percentage of fasciations in a hereditär}' race, and the 

 finest specimens are produced by pot culture, rich soil and subsequent 

 transplantation (de Vries, 1899, M. T. 2, p. 501). 



Nicotiana tabacum fasciata furnishes especially favorable material 

 on which to test out some of these ideas and throw further light on 

 the interpretation of the facts, for in this race, there are so many 

 structures on which reaction-phenomena can be noted. The experimental 

 cultures of this race have nearly always been grown beside the normal 

 402 race, and it is understood that both races (300—309 and 402) 

 under all the environments tested, constantly show the differences noted 

 in the preceding descriptions. 



Commercial growers of tobacco fan their seed, sowing only the 

 heaviest. In my work, unselected seed was planted in seed pans. 



