AComparativeStudyofVenationinThunbergii,Latifolius,AurantiacusandSemperflorens

A comparative study is made of the four cultivars of Osmanthus blossoms, namely the Thunbergii, Latifolius, Aurantiacus and Semperflorens to find out about their leaf venation. The findings showed that all of the four are brochidodromous camptodromous pinnate with a straight and unbranched primary vein; secondary vein is sharp and camptodromous, tertiary vein is reticulate, orthogonal. The loop of secondary vein is rounded by the loops of tertiary vein or quaternary vein. The intersecondary veins are all compound; the marginal ultimate venation takes the shape of a knotted ring; the teeth have no glands and the teeth tips are simple and within the teeth the primary vein has a tertiary or quaternary rein which point toward the middle and go right into the teeth without any accessory reins; the semperflorens is rather different from the other three varieties: the former has a killer tip while the other three have a sword-t ip-shaped leaf tip; the upper angle of Osmanthus fragrans var. semperflorens is sharper than the lower part, the angle variation of the other three kinds is approximately the same, indicating that the former has a rather distant genetic relationship with the latter three, and the latter three are genetically closer compared with the former.