344! ATTOGAMY, 



on the i-ougli svirfaoo of the pad of tissue in the middle of the tlower ew\sos, the 

 polHuated stigiw.-is turn bivwn, and the period of bloom for that pu'tiouljvr flower 

 comes to an end. The imperfect st^\n\inifei>otis tlowers do not unfold until all the 

 hermaphrodite tlowers aiv o\-er, a fact which can only be iuterpivted as indioating 

 that their pollen is to be devoted to the fertilization of pivtojiynous hermaplu'odite 

 flowers of other individuals which are still in the tii-st. st-age of flowevinjy. Fail's 

 Parsley (-f?/("«T Ci/uapium. see tig-s, 2SH1 '*>•'• ^) ditlers fixMu the Venus" Oomh and 

 the other annual Umbellifers abo\e referred to in that all the llowei-s of an uutbol 

 ai-e hermaphrodite, and that the tilamentv^, which in the bud aiv tucked in like 

 springs (,tig. 201)*), not only straighten out when the llower opens, but elongate, 

 and thus raise the anthers to a higher le\-el than the stigma. Also in Fool's raraloy, 

 as has been mentioned before, the anthers are not laid right against tlie stigmas, 

 but remain a little higher, and let their pollen fall upon then> from above (see 

 fig. 296"). This at least is what I saw in the case of the conunou Fool's Pai'sley or 

 ^Etliiu<a Ci/napium: the small ^Ktlia^a srtjftalix, on the other hand, acoonling to 

 my observation, much n\ore frequently brings its anthers into contact with tlie 

 stigmas in the same m.anner as the Venus' Oomb (see tig. 2!Hi*), 



Autogamy of tl^e same type as tliat described in (he above inst«Bces of imnual 

 Umbelliferse also takes place in nuiny small-llowered Bod-str.-iws (^e.g. Oaliwm infos- 

 tarn, 0. Mollugo, 0. tru'onw), in the Dodder {Cn.^ciUa), in the Alpine Enclmnter's 

 Nightshade {GirccBa alpiiia), and in .\grimony (A<iriiu,0)ita Ki(patoiHa). Of tlie 

 Enchanter's Nightshade (see figs. 297 ^^ -••''■ ■*), it is only needful to note tliat the 

 number of stamens is limited to two, and that sometimes one anther alone is laid 

 upon the stigma (207 '), but not infrequently both subserve the purpose of auto- 

 gamy in that manner (207 '). In the latter case the stiguta looks as if it wore 

 grasped by the two limbs of a, pair of tongs. The flowers of Agrimony have from 

 12 to 20 stamens, and are protogynous. Tlu^ anther-tila.menta are very slightly 

 incurved, each corresponding to about a sixth part of tlie circumfoi'enoe of a oiirlo 

 (tig. 297''), but as soon as dehiscence takes place the filaments bend one nltoi- 

 another towards the centre of the flower (see fig. 297 ^) until they are in tlie form 

 of semicircles, and some of the anthers cox'cred with pollen come into direct contact 

 with the stigmas, which are still in a receptive condition (fig. 207 "). Soon after tlie 

 stigmas have thus been furnished Avith pollen the a,ntherH drop off the filaments, 

 and the latter coil up still more as is shown in iig, 297 ^\ 



Several species of Stonocrop (e.g. 8edum annuvm,, S. atratwn, S. daayphylliim), 

 and some House-locks (e.g. Sempervivum. montanuin, S. RiUhenioum) have two 

 kinds of stamens in each flower, namely, those inserted in front of the sepals and 

 those inserted opposite the petals. The anthers of the former are the first to open, 

 and as they are quite close to the stigmas only a slight inclination of the curved 

 filament is necessary to bring about autogamy. After a deposition of pollen upon 

 the stigmas has already taken place, the filaments opposite the petals also curve 

 over inwards, and the nnlher.s, which meantime have undergone dehiscence, lU'O 

 held right over the stigmas. But, seeing that the latter a.ro by this time withered 



