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Show 324 FERTILITY OF CROSSED CHAP. IX. A second table, G, gives the relative fertility of flowers on crossed plants again cross-fertilised, and of flowers on self-fertilised plants again self-fertilised, eith r in the first or in a later generation. I-Iere two causes combine to diminish the fertility of tho selffertilised flowers; namely, the lesser effi cacy of pollen fron1 the same flower, and the innate lessened fertility of plants derived from self-fertilised seeds, which as we have seen in the previous Table D is strongly 1narked. ~rhe fertility was determined in the same Inanncr as in 'fable F, that is, by the average number of seeds per capsule ; and the same remarks as before, with respect to the different proportion of flowers which set capsules when they are cross-fertilised and self-fertilised, arr here likewise applicable. TABLE G.-Relative Ilertility of Flowers on Crossed and Sel f ertilised Plants of the First or some succeeding Gen erution ; tl,e forme'f' being again f e?·tilised with Pollen from a d'istinct I lant, and the latter agoin with tlteir own Pollen. Fert'ildy j ndged of by the average Numrer nf Seeds p er Capsule. F(rtility of Crossed Flowers taken as 100. IPOMCEA PURPUREA- rrossed and self-fertilised fl ower s onl t~ e crossed and self-fertilised plants of the 1st generation v1eldecl sE-eds as . . . . . . . . . . . . lPC)]VI CEA PURPUREA-crossed and self-fertilised fl ower s on l the crossed and self-fertilised plants of the 3rd generation 'y ielded seeds as . . . . . . . . . . . . JPOM<EA PURPUREA-crossed nnd self-fertilised fl owers o n~ the crossed aud self-fertilised plants of the 4th gener ation yielded seeds as . . . . . . . . . . . . JJ>OM<EA PlJRPURgA-crossed and self-fertilised fl ower s on l the crossed nnd elf-fertilised plants of the .5th gener at ion ! y ield ed seeds as . . . . . . . . . . . . ~1i ~IULU S LUTEUS- cross t:!d and self-fertili sed flow ers on th e ~ crossed and self-fertili sed plants of the 3rd genera t ion I yield ed seeds as (hy weight) . . . . . . . . 1\11MULUS LUTEUS-same plants treated in the same manner \ on following year yielded seeds aR (by weight) . . . ) MJMULUS LllTEUS- crossed and self-fertili sed fl owers on th e ~ rrossPd ancl self-fertili sed plants of the 4th g(!ner ation y ield ed seeds as (~y weight) . . . • . . . . 100 to 93 " " 94 " " 9+ , , 1 U7 , " o::i " " 34 " " 40 CHAP. IX. AND SELF-FERTILISED FLO)VERS. 325 T .-\BLE G- cord inued. VIOLA TlliCOLOR·-~r?s. e.·d· and self-fert~lised fl owers on the l l crossed and selt-fertth::;eu plants ot t.he 1st o·ener ation 100 to G9 yielded seeds as • . . • . . . . . 5 • • • 1 DIANTHUS CALWOPHY. LL~_S·:-c~·~ssed and se] f-fertili sed {-J o wers ~ ~ on the ero:sed and selt-fertlltsecl plants of the 1st 2:ener a- G ~ u " " ;) tion yi eldecl seeds as . . . • . . . . . . . DIANTHUS' CARYOPil Y~L US-flowers ?n self-fertili sed pl ants ~ ~ of t~e 3rd gener .at JOn _cross.e~ by 1~1te rc rossed pl ants, and ( , , 97 othe1 flow ers agam self-fertilised yteld ed seecls as . . Jj of the 3rd gener atiOn cr ossed by a fr esh st ock, and other 1 , , 127 DIANTHU~ CARYOlliY!'LUS-fl owers on. se lf-fertili secl plant s ~ flowers again self-fertilised yielded seeds as . . . . LATHY~.us ODOH.ATUS~cro_s~ecl and se lf-f?rtiliseu fl owers on~ l the c1 os ·ed and self-fert1hsed }Jlants ot the 1st generation G ~ yt.e lde d seeds as . . . . . . . . . . . . " " ;) LODELIA RAlVIOSA-c~·os~e.d a nd sel f-fertili sed fl owers on the ~ ct.·ossed and self-fertilised plants of the 1st generation 1~ 0 yte ld ed seeds as (by weight) . . . . . . . . I '' " G t~e crossed and se lf-fertilised plants of the 1st. generation 68 PETUNIA VIOLAC!!:A-cr ossed and self-fertilised fl owers on~ ytelUed seeds as (by weight) . . . . ~ . . . " " the Clvssecl and selt-tertlll se cl nlants of the 4th D'eneration 70 PETUNI~ VIOLACEA--;-c~· os~c.d and self-fertilised fl owers on~ !" b " " "-' yielded seeds as ( by weight) . . . . . . . . PETUNIA VIOLACI£A-flowers on self-fertilised plants of th e ~ · 4th. gene1~a~io~ ~rosse ~ by a fr esh st ock, and oth er flowers , , .f. ~ agmn selt-fertlhsed ytelded seed::; as (by weig ht) . . . NICOTIANA TADACUM- t:rossed and self-fertili sed fl ower s onl t~e crossed and se lf-fertili sed plants of the 1st generation , , 97 ytelded seeds as (by weight) . . . . . . . . NICOTIANA TABACUM- fl ov.:ers on self-fertili sed plants of the 2nd generati on crossed by intercrossed pl ant s, and f o.ther. flowers again se lf-fertilised yielded seeds as (by es - " " 11 0 t1matton). . . . . . . . . . . . . . the 3rd generation crossed Lv a fresh stoek and other , 110 • NICOTIANA TABACUM- fl owers on s'e lf-fertili sed plants o f~· flowers again self-fertilised yi eld ed seeds a::> (bj estimation) I " blu~ .vanety, and other flowers on the red variety self- I , , 48 ANAGALLis. COLLIN A-flowers on a red variety crosseLl by a~ fert1hsed yielded seeds as . . . . . . . . . CANNA~ ARSCEWICZI-.cro~~ed and sclf-t~rtili sed flow er s onj l the Ciossed and self-fertJhsed plants of three generations , , 85 . taken together yielded seeds as . . . . . . . . I As both these tables relate to the fertility of fio\:ers fertilised by pollen fron1 another plant and by then own pollen, thev n1ay be considered too·ether. ~h . J b e difference between them consists in the self- |