Carpels are the parchmentlike walls of the seed cells. They vary in form somewhat as leaves do, and the terms used in describing leaves may well be applied in describing the carpels. The two sides of the seed cells correspond to the two halves of a leaf, with the axis of the fruit representing the midrib of the leaf.

Fig. 42. Abaxile core.

Cordate. A term used to describe a carpel whose two halves are heart-shaped.

Emarginate. A term used to describe carpels which are indented at the top or bottom, but too narrow to be cordate.

Mucronate. A term used to describe carpels which come to a sharp point.

Obcordate. Reversed cordate.

Round. A term used to describe a carpel whose two halves are nearly circular.