These features refer to the tenth leaf stage. The tenth leaf is the tenth true leaf produced after the cotyledons. On seedlings with alternate or spirally arranged leaves it is just simply the tenth leaf produced. On seedlings with opposite leaves it is one of the leaves in the fifth pair of true leaves produced. On seedlings with whorled leaves it will be one of the leaves in the appropriate whorl; e.g. if there are four leaves in each whorl then the tenth leaf will be one of the leaves in the third whorl.
Stipules are small growths on the stem and are generally found in pairs, one on each side of the stem at the junction of the petiole and the stem. Stipules frequently fall off early in life and following such an event, their occurrence can only be inferred by the presence of scars on the stem.