AUTOGAMT BY A OO-OPERATION OF MOVEMESTS. 



385 



AUium GhanumnoLy (see fig. 311 ^) is an example of the plants, in whose flowets 

 gnlogamy is effected by ooncnrrent movements of the pedicel and the style, the 

 fsgxsxer nndeargmng inflection, whilst the latter is inclined in the direction of the 

 gnote where tiie pollmi has been deposited. The small white flowers are lifted bnt 

 a vay litfle way above the ground; at first they face the sky, and are half hidden 

 anKngst tiie long green ribbon-shaped foliage-leaves. Xevertheless, they are 

 asadnondy song^t ont by small insects, the honey, which is secreted in little depres- 

 aons oa the snrface of the ovary, being in great request. Daring the first stage of 

 flowering crcGB-pollination alone is possible; the stigma is posted in the middle of 



^^4 flowos in tlie tinee Ence^^re stages o£ tiieir derekqme&fc wid^ lead to 

 Aniiiefig^ somevliai reduced. 



f%.9ft.— Aato^nj lesailii!^ ^ssm zb inSeetaora of iSoe pedicEi asoompaaied by ^laal toisioD of file Slam^sts: O^xga 



>aie nev ef s nsvlf ope^sd ftiver. 



tiie moatli of the flower, and its tissae is already receptive whilst the anthers are 

 still dosed and appressed to the walls of the perianth (see^fig. 311 ^ Later on all 

 flie filaments undergo inehnation towards tiie middle of the flower; the anthers 

 bmst opeo, beerane covered all over wilji the pollen which issues from their locnli, 

 and tagger form a yellow knob which oeeapies the centre of the entrance to the 

 mtedor of ttie flower, and is brushed by all intrnding insects. The stigma is at that 

 stage hidden behind the anthers (see fisr. 311 ^, and is not touched by insects. If, 

 for any reason whatever, insects do not visit a flower, antogamy takes place in the 

 tiiiid stage c^ its development. The pedicel carves over downwards and presses the 

 ^awtx against the groand, and, as a conseqaenee, tiie delicate white perianth-ieaves 

 and fifif cRm stamens are displaced, and srane of the poUen fells out of the anthers 

 «i to the lower perian^-Ieaves now resting upon iiie grouiid. The style undergoes 

 ^^it lateral, ijR. in tiiese drcumstances downward, inclination and the final result 

 rf all these movements is tiiat the stigma is brought into contact either with the 



Vol n. 75 



