entirely lost sight of. Only a very few agriculturists have applied it:
among these are Patrick Shirreff ("Die Verbesserung der Getreide-Arten",
translated by R. Hesse, Halle, 1880.) in Scotland and Willet M. Hays
("Wheat, varieties, breeding, cultivation", Univ. Minnesota, Agricultural
Experimental Station, Bull. no. 62, 1899.) in Minnesota. Patrick Shirreff
observed the fact, that in large fields of cereals, single plants may from
time to time be found with larger ears, which justify the expectation of a
far greater yield. In the course of about twenty-five years he isolated in
this way two varieties of wheat and two of oats. He simply multiplied them
as fast as possible, without any selection, and put them on the market.

Hays was struck by the fact that the yield of wheat in Minnesota was far
beneath that in the neighbouring States. The local varieties were Fife and
Blue Stem. They gave him, on inspection, some better specimens,
"phenomenal yielders" as he called them. These were simply isolated and
propagated, and, after comparison with the parent-variety and with some
other selected strains of less value, were judged to be of sufficient
importance to be tested by cultivation all over the State of Minnesota.
They have since almost supplanted the original types, at least in most
parts of the State, with the result that the total yield of wheat in
Minnesota is said to have been increased by about a million dollars yearly.

Definite progress in the method of single-ear sowing has, however, been
made only recently. It had been foreshadowed by Patrick Shirreff, who
after the production of the four varieties already mentioned, tried to
carry out his work on a larger scale, by including numerous minor
deviations from the main type. He found by doing so that the chances of
obtaining a better form were sufficiently increased to justify the trial.
But it was Nilsson who discovered the almost inexhaustible polymorphy of
cereals and other agricultural crops and made it the starting-point for a