14 ATMOSPHERICAL CHANGES INDICATED BY PLANTS. 



versal rule for the whole world. The minor changes in the atmo- 

 sphere, with which our variable climate makes us so familiar, are so 

 accurately foretold by many plants, that the attention devoted to its 

 consideration will be amply repaid Ijy the discovery of such interest- 

 ing properties. 



" Flowers shrinking from the chilly night 

 Droop and shut up, but with fair mornini^'s touch 

 Rise on their stems all open and upright." — Montague. 



The sensitive indications developed by the common Pimpernel 

 (Anagallis arvensis) are so well known, that it has been entitled 

 " The Poor Man's Weather-glass." It is 



"Of humble growth, though brighter dyes, 

 But not by rural swains less prized. 



The trailing stems allure 

 Of Pimpernel ; whose brilliant flower 

 Closes against the approaching shower, 

 Warning the swain to sheltering bower, 



From humid air secure." — 3Ioral of Floicers. 



Its bright tiny flowers close some hours before the occurrence of 

 rain, and "go to sleep," or close up soon after noon, expanding 

 again at seven in the morning. 



The Germander Speedwell (Veronica Chamsedrys), so universal a 

 favourite in every hedge-row, closes its lovely blue flowers on the ap- 

 proach of rain, and as surely opens them again when the storm is 



overpast. 



" Not for thy azure tint, though bright. 

 Nor form so elegantly light, 

 I single thee, thou lovely flower, 

 Prom others of the sylvan bower, — 

 Thy name alone is like a spell, 

 And whispers love, in " ' Speed-thec-Well.' " 



It is observed that if the Siberian Sowthistle shuts at night, there 

 will generally ensue fine weather on the next day ; and if it opens, 

 cloudy and rainy. If the single African INLarygold remain shut after 

 seven a.m., rain may be expected. If the Trefoil contract its leaves 

 during the day, heavy rain generally ensues ; and Lord Bacon has 

 observed, that its stalk is more erect against rain. 



The common Chickweed (Stellaria media), in fine weather, sup- 

 ports its flowers upright, and open from nine in the morning until 

 noon ; but if it rains they remain closed, after rain they become 

 pendant. This plant, it is said, affords " a remarkable instance of 

 the sleep of plants, for every night the leaves approach in pairs, in- 

 cluding within their upper surfaces the tender rudiments of the new 

 shoots ; and the uppermost pair but one at the end of the stalk is 

 furnished with longer leaf-stalks than the others, so that they can 

 close upon the terminating pair and protect the end of the branch." 



The Purple Sandwort (Arenaria rubra) is another example of a 

 true prophet prior to a coming shower. The flowers, a beautiful 

 rosy-purple, expand themselves only when the sun shines, and close 

 again when the shades of evening draw in, or before a coming 

 shower. 



