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IOWA ACADEMY OF SCIENCE Voi,. XXIX, 1922 
of Mendel, is that of John Goss of Hatherleigh, in Devonshire, 
England, with garden peas. In the summer of 1820, Goss pol- 
linated flowers of the Blue Prussian variety with pollen of a dwarf 
pea known as Dwarf Spanish, obtaining, as the result of the 
cross, three pods of hybrid seeds. In the- spring of 1821, when he 
opened these pods for planting, he was surprised to find that the 
color of the seeds instead of being a deep blue like those of the 
female parent, was yellowish white like those of the male. How- 
ever, the parents growing from these seeds in that season “pro- 
duced some pods with all blue, some with all white, and many 
with both blue and white peas in the same pod.” Here was 
evidently a plain discovery of the fact of segregation, according 
to what later became known as Mendel’s law. The following 
spring (1822) he separated the blue peas from the white, sowing 
the seeds of each in separate rows. He found that the blue seeds, 
which we should now call the “recessive,” produced in turn only 
blue seeds; while the white seeds, or “dominants” as they are now 
called, “yielded some pods with all white, and some with both 
blue and white peas intermixed.” Here, then, is the typical case 
of the segregation of the heterozygotes or hybrid dominants. 
In 1819 the Physical Section of the Royal Prussian Academy 
of the Sciences offered a prize for an answer to the question — 
“Does hybrid fertilization occur in the plant kingdom?” On the 
third of July, 1826, the Academy’s prize was conferred upon 
Dr. A. F. W iegman, physician of Braunschweig. Wiegman re- 
gards chance crossing in nature, between species or sorts of plants, 
as having given rise to new agricultural races. “It appears from 
my experiments,” he says, “that many species, or constant sub- 
species, e.g., Pisum arvense, Vicia leucosperma, Vicia faba, as 
well as the most of the varieties of cabbage and the cereals, whose 
origin is unknown, possibly are hybrid plants, which have been 
produced upon our fields and in our garden, through the proximity 
of a few related plants, and which have remained constant.” 
Regarding the matter of dominance, Wiegman incidentally re- 
marks upon the case of crossing of two species of Dianthus, 
where “the form of the father has almost entirely suppressed 
that of the mother.” According to Wiegman’s statements “there 
occurs even immediately after fertilization, an alteration in the 
form and color of the seed, and in the form and size of the pods, 
which is especially unmistakable in the case of the leguminous 
plants, although otherwise the fruits and seeds of hybrid plants 
