of the well-known lily-of-the-valley, and also was true of the var- 
ious species of strawberries until they were crossed. Only after 
careful isolation of single plants and several generations of pur- 
ification by inbreeding, does like begin to produce like, and even 
then the results are sometimes discouraging. By such methods, 
variability is reduced to a minimum, and a comparatively pure 
breeding strain or variety is created. 
For centuries scientific men have grappled with this problem 
of variation, attempting to discover some law or order in all the 
seeming chaos that it produces. When certain characters were 
common to both parent and offspring they called it heredity, but 
often other characters appeared— characters that had been un- 
known to the ancestral line tor generations. The breed of 
chickens called Blue Andalusian presented an extremely perplex- 
ing problem, as about one-fourth of the eggs always produced 
sooty whites, another fourth blacks, and only approximately one 
half gave typical Andalusians. No amount of selection and in- 
breeding reduced the number of these off-types. Such cases 
made men despair of finding any laws of heredity or variation. 
As soon as one was formulated, exceptions arose which shortly 
buried the law by their numbers. Superstition was common. 
Birthmark blemishes faintly resembling strawberries appeared 
on children due, so it was said, to mothers having seen or 
dreamed of strawberries preceding their birth. Hours were spent 
by mothers before beautiful statues and paintings, that the un- 
born child might be beautiful. The breeding of fine mares to 
scrub or to undesirable stallions for a single time was supposed 
later to mar the offspring of these same mares by fine stallions. 
Experiments by scientific men were few and far between, and 
largely resulted in collections of interesting but isolated facts. 
What was especially needed was some one who could arrange 
and correlate these facts into a general law. In other words, the 
rosetta stone had not yet been found. No one had yet discovered 
the key by which these facts could be interpreted. “Heredity,” 
wrote Balzac, “ is a maze in which science loses itself.” 
Then came the Augustinian monk, Gregor Mendel, a man with 
a mathematical, analytical mind. With the insight and perse- 
verance characteristic of genius, he outlined seme experiments 
which he believed would throw some light on the inheritance of 
characters and bring order out of chaos. After much experi- 
menting, he selected peas as the material most favorable for his 
purpose, made certain that the varieties bred true in certain well 
defined characters, and proceeded with some crossing experiments 
between varieties differing from each other in one or more of 
these tested, true-breeding characters. When a plant with red- 
dish-purple flowers was crossed with one having white flowers, 
the offspring were not pink, light purple, or intermediate, as one 
might naturally expect, but all were reddish-purple flowered and 
