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In his second memoir Linsser (i869) begins by showing that many 
well-recognized facts have been found which harmonize with the 
conclusions at which he had previously arrived. Thus, in the first 
and second halves of the eighteenth century the northern limit of the 
cultivation of grain had not passed beyond latitude 60° 30’ N., and 
many unsuccessful attempts had been made to ripen the grains im 
more northern regions; but in 1829 Erman found a small successful 
beginning going on at Yakutsk, and since then it has spread in all 
directions and has extended to barley, oats, rye, and wheat. Similarly 
in Lapland the cultivation of grain succeeded only for a long time in 
the southern regions, but now it extends to the north and even 
among the mountains In Lapland this cultivation succeeded only 
when the seed was brought from near by, not from a distance, and 
Von Baer says that it was commonly said that the grain had aceli- 
matized itself, or, as he expresses it, “ It seems to me that gradually 
a quick-ripening variety or ‘ sport’ has developed that is not injured 
by the early frosts of summer nights.” 
F. C. Schiibeler (1862) in his memoir on the cultivated plants of 
Norway states that in 1852 the seed of yellow maize brought to Nor- 
way from Hohenheim, near Stuttgart, was sown on the 26th of May 
and reaped one hundred and twenty days later, but after continued 
annual cultivations, in which every harvest came a little earher than 
its predecessor, Schiibeler, in 1857, sowed the seed on May 25 and har- 
vested it in ninety days, while the seed of the same variety brought 
fresh from Breslau and sowed on the same date ripened only after 
one hundred and twenty-two days. Even Kalm had remarked that 
maize when transported from a southern to a northern latitude 
gradually overcomes the difficulty of ripening and eventually gives a 
nearly constant variety of grain. 
Morren, in the Belgique Horticole (1859-60), says the principai 
problem to be resolved in Norway in the amelioration of its agricul- 
ture is the introduction of new varieties and the development of 
-precocity. This precocity increases year by year, as if the plant could 
not all of a sudden obey the new climatic influences under which it 
had been brought. Plants cultivated many years in succession under 
a northern climate when transported to a southern climate preserve 
something of their former rate of development and are more preco- 
cious than plants of the same species that have remained in their first 
situation. Just as wheat carried from Germany northward into the 
Baltic Provinces of Russia fails to ripen its grain, so grain carried 
from the valleys up to the highlands in Switzerland fails to ripen. 
Bastian quotes an old English author who says that in the accli- 
matization of plants the graduation of the process is the principal 
necessity, and that a sudden acclimatization in a new home is impos- 
sible, so that a plant gradually learns to live in a climate in which 
