536 TJEBBES, KOOIMAN, ERFELIJKHEIDSONDERZOEKINGEN BĲ BOONEN. III 
een extreemgeval van bontbladigheid? Of hebben we hier voor ons 
een voorbeeld van chemischen invloed der onderstam (normale 
boon) op de entloot ? 
We kunnen deze vragen nog niet beantwoorden. 
Echter stellen wij ons voor, ons onderzoek in dit ras voort te 
zetten. Wij zullen trachten, kunstmatige bastaarden te verkrijgen van 
ons albinotisch ras en andere rassen met normale bladkleur en 
hopen een ander maäl de resultaten daarvan te kunnen mededeelen. 
| We meenden, dat, hoewel het onderzoek nog niet vergevorderd 
is, zoowel de methode van enten als de soort albinisme of bont- 
bladigheid interessant genoeg zijn om er iets van mede te deelen 
Summary. 
During several years a strain of dwarf beans with pale vellow 
seeds was cultivated. This strain habitually threw a considerable 
percentage of albinotic seedlings, developing hypocotyl, cotyledons, 
epicotyl and the first pair of simple leaves, all ivory white without 
the slightest trace of green, aud dying away soon after having unfolded 
the latter. 
In 1916 the seeds of three of the surviving normal green plants 
of this strain were gathered separately. 
Sown in 1917 and 1918 two of these lots gave normal seedlings 
only, Of the third one, gathered from the plant E.9, the 35 seeds 
sown in 1917 gave 26 greens and 8 ivory whites, while the rest 
sown in 1918 produced about 3 green seedlings: 1 white, an exact 
count being impossible in that year on account of unfavorable con- 
ditions causing the loss of many seedlings at a very early date. 
From the results obtained we conclude to a simple mendelian 
segregation with green leaf-color as a complete dominant. 
For further study albinotic seedlings were grafted on green ones 
of a somewhat (about 2 weeks) older age. This succeeded best in 
those cases in which we cut both plants obliquely across and joined 
them in the way shown on photo A. In the beginning the graft was 
held in position by means of a strip of raffia. It will be noted that 
the white plant has been cut across the hypocotyl, so that it 
could profit of the food present in its cotyledons until it was suf: 
ficiently joined to derive food from the green plant on which it was 
fixed in the closest possible proximity of the leaf producing this food, 
RÉ en 
