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Show Vlll OONTENTS. CHAPTER XII. GEN ERAJ~ HEf:!ULT~. . . . . to be beneficial, and self-ferti lisation iH-Oross- fertihsatlOn lJfO \ ed d· .ec tly I·n the means by which . . A\ l' d pecies luer area junous ---:- . ~~ ~ oured : nd self-fertilisation avoirledcross- fertihsatlOn 18 fav d nd on the decrrc · The benefits and evils of the t wlo lproeestse~ rcl~: evil cfl'ccts onot . ff f t' . n the scxua e em en .s of dl eren la Ionb.l t' of morbid t endencies in the parents-d to the com ma IOn . 1 1 ue . of 'the conditions to which plants are subJectc< w len Natu:e t ther l·n a state of nature or under cnlture, and err owl ncr ncar ocre ' · ,, t' · tl t:> <::' , ::'Jh ..J't' s - Theoretical consluera !ODS w t 1 the effects ot sue conui wn . .,. l t - t to the interaction of diffcrentmted sexual e emcn s respe~ l l , Genesis of the two sexes - Close r.orresl on- Pract lCa es::-ons - lf f t T d e between the effects of cross-fertilisation a~d so - cr 1 lS.fl-t .enc nd of the lecritimate and illeaitimate urnong of he tel ~>- IOn, a o . h b 'd . Pacro 4 G-~6V styled plants, in comparison with y n umons , o } NDEX •• Page 471-48'2 THE EFFECTS OF CROSS AND SELF-FERTILISATION. ERRATA. PAGE 35, Table VI., bottom of second column, for. " 495 •13" read " 495 • 25." 121, twelve lines from bottom of page, for" fertilised" read "self-fertilised." 162, Table LVII., bottom of third column, for" 158·'16" read" 158•'15." THERE is wejghty and abundant evidence that the flowers of most kinds of plants are constructed so as to be occasionally or habitually cross-fertilised by pollen from another flower, produced either by the same plant, or generally, as we shall hereafter see reason to believe, by a distinct plant. Cross-fertilisation is sometimes ensured by the sexes being separated, and in a large n urn ber of cases by the pollen and stig1na of the same flower . being matured at different times. Such plants are called dichogamous, and have been divided into two sub-classes: proterandrous species, B |