7. Siamensis, sn, is a recessive character of variable expression obtained from an Amargo strain. Of the double seedlings, the "paracite twin" aborts early in some instances, leaving normal appearing individuals. A homozygous strain of sn exhibited the following types:

• Seedlings with marked duplications - 12
• Seedlings with different abnormalities - 32
• Seedling normal - 1.