The primitive exarch and diarch haplostele with cross-like metaxylem exists in the lower part of CNZ.
在子叶节区下部存在原始的外始式二原型十字形单中柱。
2
Adonis amurensis is perennial herb, Its roots are nearly primary structure in the whole life, Primary Xylems of main root and lateral roots of one year seedling are diarch.