A leaf choice experiment was conducted and the behaviour of the female weevil was observed before she commenced cutting. The female always performed a sequence of stereotype behaviours preceding cutting. The results of this study indicate that the female firstly decides the number of eggs to be laid in the cradle and then starts looking for a leaf suitable for that number of eggs. While the female is making a cradle, she measures and perceives for different purposes three different distances on the leaf (or something that represents each of them: 1) the length of the whole leaf, i.e. the criterion of adequacy of a leaf for a cradle, 2) the leaf width, i.e. the criterion of adequacy of a leaf for a two-egg cradle, and 3) about 1 cm along the main vein from the leaf base, i. e. the determinant of the cutting site. These three are probably measured while the female is performing the stereotype walking. Measuring both leaf length and leaf width amounts to predicting the shape and the size of the cradle.