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years, Dr. Nilsson-Ehle produces for the Station of Svalov 

 new combinations of genetic factors, by crossing - experiments 

 with a definite aim ; which obviously is a much more certain 

 way than the happy-go-lucky selections from niixtures of Svalofs 

 earlier clays. 



But it is well to remember that Dr. Nilsson-Ehle could 

 do his excellent work as well in Madeira or in California as in 

 Svalof ; and with quite the same results for his countri, if only 

 he sent his seeds there to be tested by his agricultural experts. 

 For any country, wishing to produce varieties more suitable 

 to different conditions in its diverse parts ; it is quite possible ; as 

 well as most economical, to have one single easily accessable 

 Station at which an experimental breeder can make a great 

 collection of diverse varieties, and produce new ones for the 

 agricultural experts at the different local experiment-stations to 

 try and compare. 



I would especially emphasize the need of having a great 

 collection of types, imported from other countries, quite indepen- 

 dently from their greater or lesser importance in their own 

 country. I am quite certain that in trying only „good" imported 

 varieties ; one considerably limits one's chances to find a suitable 

 onc for one's own ; probably somewhat different conditions. It is 

 obvious that, whenever a choice is made between a great number 

 of different biotypes, a great number of them are rejected, which 

 would be found excellent if only the exact locality for which 

 they would fit could be ascertained. 



The requirements of a variety of wheat are extraordinarily 

 different for different localities. In one place the straw has nearly 

 the same value as the grain ; and a wheat is required, which will 

 respond to a dose of artificial fertilizer by a heavy yield of good 

 straw, at another place the straw has no value whatever ; and the 

 same wheat might be far from profitable in favorable years. In 

 some localities even the wheat with the weakest straw does not 

 lodge and there a variety may be excellent which at other places 

 would be hopelessly ruined by heavy rains. 



In arid and semi-arid regions everything depends upon the 

 price of the water available for irrigation. Whereever water can 

 be had in sufficient quantity ; and is not too expensive, it will 

 be found, that a rather longlived wheat, capable of producing a 

 good yield when irrigated will be required. Where water is 



