. Practical text-book of plant physiology. Plant physiology. REACTIONS OF STAMENS TO SHOCK 19. Fig. 6. Sections of two flowers of Opunlia. e, with stamens in normal position, d, with sta- mens bending toward the style in response to shock of rough objector insect. After Tourney. Strike the terminal leaflets of a normal specimen of Biophytum so lightly that no reaction ensues and repeat at intervals to de- termine the memory, or time during which the stimulus-effects are retained and cumulated, finally producing full excitation. 26. Reactions of Stamens of Opuntia to Shock. The flower of Opunti
. Practical text-book of plant physiology. Plant physiology. REACTIONS OF STAMENS TO SHOCK 19. Fig. 6. Sections of two flowers of Opunlia. e, with stamens in normal position, d, with sta- mens bending toward the style in response to shock of rough objector insect. After Tourney. Strike the terminal leaflets of a normal specimen of Biophytum so lightly that no reaction ensues and repeat at intervals to de- termine the memory, or time during which the stimulus-effects are retained and cumulated, finally producing full excitation. 26. Reactions of Stamens of Opuntia to Shock. The flower of Opuntia contains a single central style sur- rounded by a number of shorter stamens. Bees or other insects entering the flower in quest of honey pass down the style, touch- ing the filaments of the sta- mens. As a result of such stimulation the stamens curve inwardly toward the style, forming an arched cage with the style in the center, in which the bee is imprisoned. In brushing aside the anthers to escape the bee carries away some of the pollen, which may be left in another flower, effect- ing cross pollination. The curvature of the filaments is so rigid that the bee may be held for several minutes, and its struggles act as repeated stimuli, causing tetanus of the filaments. After a time, however, the organs become accustomed to the repetition of the stimuli, the tetanus is relaxed and the filaments straighten out to their original po- sition, allowing the insect to escape. If it is not irritation of the possible to observe this action, imitate the behavior stigmatk sur- 0f the bee with a small wire or wooden Similarly sensitive stamens may be found in Mammillaria, Echinocactus, Echinocereus and other reactions may be seen in Berberis, and in some of the Cichoria- 'Touiney, J. W. Sensitive stamens in the genus Opuntia. Asa Gray Bull. 7 : 35- l899- Fig. 7. Pis- til of Mimulus. b, expanded po- sition, a, after faces. Belzung. After. Please note that these images are extrac
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