Ovule of Taxus

Ovule of Taxus:-

- The ovule is somewhat rounded or oval in shape and orthotropous. A single thick integument is present. Integument is free from the nucellus right up to its base forming a long micropyle. The integument is differentiated into outer fleshy, middle stony and inner fleshy layers. Two vascular strands enter the integument from the base of the ovule and reach up to its top.

- A ring-like outgrowth develops from the base of the integument. It surrounds the entire ovule. It is called ‘aril’ or ‘cupule’ . Aril is green and saucer-shaped when young but at maturity it is red and cup-shaped.

- The aril also receives two vascular bundles but they are very minute and rudimentary. Pollen chamber and nucellar beak are absent in Taxus. The apex of the female gametophyte changes into a flask-shaped structure called tent-pole. The tent-pole disappears in the later stages.