[_Mimosa_. I. 301. The sensitive plant. Of the class Polygamy, one house. Naturalists have not explained the immediate cause of the collapsing of the sensitive plant; the leaves meet and close in the night during the sleep of the plant, or when exposed to much cold in the day-time, in the same manner as when they are affected by external violence, folding their upper surfaces together, and in part over each other like scales or tiles; so as to expose as little of the upper surface as may be to the air; but do not indeed collapse quite so far, since I have found, when touched in the night during their sleep, they fall still further; especially when touched on the foot-stalks between the stems and the leaflets, which seems to be their most sensitive or irritable part. Now as their situation after being exposed to external violence resembles their sleep, but with a greater degree of collapse, may it not be owing to a numbness or paralysis consequent to too violent irritation, like the faintings of animals from pain or fatigue? I kept a sensitive plant in a dark room till some hours after day-break: its leaves and leaf-stalks were collapsed as in its most profound sleep, and on exposing it to the light, above twenty minutes passed before the plant was thoroughly awake and had quite expanded itself. During the night the upper or smoother surfaces of the leaves are appressed together; this would seem to shew that the office of this surface of the leaf was to expose the fluids of the plant to the light as well as to the air. See note on Helianthus. Many flowers close up their petals during the night. See note on vegetable respiration in Part I.] Veil'd, with gay decency and modest pride, 310 Slow to the mosque she moves, an eastern bride; There her soft vows unceasing love record, Queen of the bright seraglio of her Lord.-- So sinks or rises with the changeful hour The liquid silver in its glassy tower. 315 So turns the needle to the pole it loves, With fine librations quivering as it moves. All wan and shivering in the leafless glade The sad ANEMONE reclined her head; Grief on her cheeks had paled the roseate hue, 320 And her sweet eye-lids dropp'd with pearly dew. --"See, from bright regions, borne on odorous gales The Swallow, herald of the summer, sails; [_Anemone_. l. 318. Many males, many females. Pliny says this flower never opens its petals but when the wind blows; whence its name: it has properly no calix, but two or three sets of petals, three in each set, which are folded over the stamens and pistil in a singular and beautiful manner, and differs also from ranunculus in not having a melliferous pore on the claw of each petal. ]