SEARCH
0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Prev | Current Page 375 | Next

Vries, Hugo de, 1848-1935

"Species and Varieties, Their Origin by Mutation"

According to the
rule, these will produce imperfect crowns of secondary pistils. The
result of any culture will thus be dependent to a high degree on the
number of individuals per square meter. I have sown two similar and
neighboring beds with the thoroughly mixed seeds of parent-plants of the
same strain and culture, using as much [394] as 2.5 cu. cm. per square
meter. On one of the beds I left all the germinating plants untouched
and nearly 500 of them flowered, but among them 360 were almost without
pistillody, and only 10 had full crowns. In the other bed I weeded away
more than half of the young plants, leaving only some 150 individuals
and got 32 with a full crown, nearly 100 with half crowns and only 25
apparently without monstrosity.
These figures are very striking. From the same quantity of seed, in
equal spaces, by similar exposure and treatment I got 10 fully developed
instances in one and 32 in the other case. The weeding out of
supernumerary individuals had not only increased the percentage of
bright crowns, but also their absolute number per square meter. So the
greatest number of anomalies upon a given space may be obtained by
taking care that not too many plants are grown upon it: any increase of
the number beyond a certain limit will diminish the probability of
obtaining these structures.


Pages:
363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387