| Show SENSITIVE PLANTS humility as a typified by tile areek aleck gentle land anil shrinking mimosa the sensitive plants mimosa budica find sensitiva senst tiva ire are among tn ionn tho the buiest interesting te products of the vegetable kingdom nearly every one has seen these graceful and ami humble children of nature and touched their tender shrinking leaves with in an experimenting hand band but very few havo have taken the tha trouble to examine examine them as a they deserve the botanist bol anist restrained perhaps by pity for their humility seems to have seldom used his section knife and forceps on them and while other wot wonders iders of the plant world have been fully investigated the mimosa remains almost unknown the mimosa is a native of BL brazil aZil but it has ha lon long been an occupant of our greenhouses Cs in III grace of aorl form and beauty of color u v ether plant cesiL it its tender leaflets shri and droop it at tile the slightest 0 touch like a mock meek spirit from the worlds gaze its 1 graceful feather shaped leaves in con commo inlo i with most similarly shaped leaves of I 1 the be or pea tribe to which botanical order the Alim mimosa belongs bo longs 0 closest close at tile the approach of darkness and its extreme sensitiveness is but in an extension of this peculiar plant sleep wind or rain causes its loaves leaves to close and its stalks to droop when suddenly shaken by tile the wind the leaflets and leafstalks leaf stalks fall simultaneously the same saino effect is seen when a plant is put into a darkened room during J the ho day A strong light from a paraffin limp was placed near two plants of mimosa sensitive sensitiva at ni nihl night hl after thirty minutes had elapsed one of the plants the more vi vigorous C orous of tho the two opened its leaves partially i the tha other or of less robust plant showed almost no feeling A plant which hid had been becci on oil an exhibition table it at a flower show shiow for two days and which was noticed to receive constant attention from some children present was found to have lost much of its excitability and did not again 0 return to lo its normal state though the plant continued in a seemingly healthy condition for about a month afterward two leaves which were nearest the cd edge cdo o of the table and consequently of fenest cst tou touched clied by bf the childrens fingers I 1 were completely immobile for ten days after the show the vapor of chloroform prussic acid ether and nicotine irritates tile tha leaves ana in some cases destroys their mobility A little chloroform dropped on the bise of a leafstalk causes it to droop and the leaflets leable beginning at the apex and proceeding to to the base of the leaf close in succession A plant tho the loaves leaves ot of which were lica vily chloroformed chloro formed several times withered and died in a few days the suns rays concentrated in a lens and thrown on a leaf cause it to contract quickly the cause of the peculiar excitability of sensitive plants and the center ut of its fiction action are still undetermined various theories have been adduced to explain them D dr r theory is most inot favored by botanists of the present day his explanation is that tile the pr principal ilici point of mobility exists in the 11 little littie swellings situated at the babig bw s of the common and partial parti il leaf stalks this swilling g or is formed of delicate cellular tissue he says that the agency 0 pro producing ducin 9 the mobility y is in ill the ho ligne ligneous part of the central system of this find and in certain tubes supplied with nervous corpuscles corpus cles ser serving viii 0 for the transmission of the sap sai dr balfour says in the at the bases of the leaf stalk tile tho vascular V bundles are disposed in a circle near the periphery and ami may bo be concerned in tho the leaf movements mechanical and chemical stimuli tire aro to act by bv inducing alterations in ili the abo contents of tho the vessels find and cell these theories aro are unsatisfactory lind anil there is still enuch room for further investigation aaion into tile tho orlain origin of the phenomena seen in tile L tile manner in which it clobes its stalks and leaves at tho the approach of darkness dark nosi is very very interest in ang e As the llie gloaming oloa e gently falls falla round tile alio plant the leaflets move upwards W ards low towards ards each other till they touch tho the secondary leat leaf stalks converge over o and blody droop till they are nearly ne irly parallel piral lello to the main leaf stalks which in ill theil turn tall fall till they pinina an ml to the grou ground tiLL thus gently and silently it foldi itself to sleep at tile tha close of day aud and rl rests ats till tho the light of morn awal cs it to ro re dewed grace and bea beauty lity Cli chambers lambers journal |
