Читать книгу Cornell Nature-Study Leaflets - New York State College of Agriculture - Страница 34

The work for this year, both fall and spring, may be the study of the cross fertilization of flowers. Choose a few of the common flowers, and let the pupils study the means by which pollen is carried from flower to flower.

In studying any flower fertilized by insects always ask: Where is the nectary? Where in relation to the nectary are the stigma and the anthers? What path must the insect follow in order to get the nectar? Do the flowers attract insects by color? By fragrance? What insects do you find visiting the flowers studied? Lessons with Plants, pp. 224-245; Plants, Coulter, pp. 109-137; Elements of Botany, pp. 182-196; Readers in Botany, Newell, Part II, p. 86; Plant World, Bergen, pp. 57-127; Ten New England Blossoms, Weed.

The cross fertilization of flowers is only one adaptation for succeeding in the struggle for existence.

Study as many other ways of insuring the continuance of a plant as is possible. Botany, Bailey, pp. 197-217; Lessons with Plants, pp. 15-20; Elements of Botany, pp. 199-212.

Study plant communities. Botany, Bailey, pp. 219-227; Plant Relations, pp. 146, 162, 168; Plant Structures, p. 313; Cornell Teachers' Leaflet, No. 19 (No. XXXV, this volume).