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Show CHAP. III. MIMULUS IJUTEUS. ot:o g 1 st genera t1'o n ·' but -fertilised plants of the ma ber any such van·e t y crossed and self myself could reme d . It must there-ardener nor h sed see · . · neither my~ . ·sed from the pure. a riation, or, JUdgmg in the seedlmgs r:ti her through ordmary v~ and self-fertilised fore have ansen eit mongst both the ~ros~e formerly existmg from its appearanceb~ through reversiOn o a plants, more proba y 81 inches and the van·e t Y· t Uest crossed P1 ~ n t wasI 'P2 ot II. t'h o ta1 1 os· t In Pot I. th~· ad 5 inches in height.! t nself-fertiliscd plant, tallest self-fertl 1Se6l inches, and the tale~ hes in height; and d lant was 2 • t 7 1nc . crosse P . d f the white vane y, . t on Mimulus m w~ich consis~rs~ instance in my expe:::: :he tallest crossed. this was the 11 st self-fertilised plant exc ts taken together were which theta e e two tallest crossed pla'; hei<>ht as 100 to 80. Nevertheless, t~est self-fertilised plants mto th: self-fertilised m to the two ta d plants were superior d !ants were crossed As yet the crossel flowers on the cross~ p . hed 1 . 71 grain. · ·t . for twe ve d f whiCh we1g . fertih Y' sules the see s o ere self-fertilised, and yielded ten capthe ~elf-fertilised pla--?-ts w . and tho seeds Twenty flowr~~~en capsules, all appeann~ po~~ 'that from an and prodnc~ them weighed only . 68 gq1~, were to the self-from ten o les the crossed see s 1 number of capsu ~ d equa . . ·ht as 100 to 40. . G neration.-See s fertilised m ~ei~j-jertilised Plants of ~he Ft!~-li:ed in the usual Grossed an se f th fourth generatiOn, er l t When the from both lots o e o osi te sides of three po s. wore found manner, were sown on t~ the self-fertilised plants d plants dl. s flowered, mos o . S veral of tho crosse . see In~ h tall white vanety. e. did a very few m to consist oft ~ belonacd to this vanety,_ asp t I was 7 inches, in Pot I. hkde~~se The ~!lest crossed plant m o to ~ide 8 inches; Pots II. an · · · d lant on the opposl 1 c1 the d the tallest self-fertilise p d were 4~ and 52, an th an I d III the tallest crosse . h ·g·ht. so that e in Pots I · an .. · and 6~ inches 1n m ' as as 100 tallest self-fert~~s=e !anest plants in the ~won~o~h:S we have average height 26 f the self-fertilised' a . . IS gene· for the crossed to 1 o~at occurred in the four prcviO~ plants a complete reversal of w . all three pots the crot~l~e cl The N rtheless 1n h lf-for 1 1se · rations. ev~ bit of' flowering before t e s~ f om the extreme retained then a f m being crowded an r e or less plants were unhealthy r~ were in consequence mo~erilo tban heat of the season, dan 1 ts were somewhat less s sterile; but the crosse pan the self-fertilised plants. CHAP, III. CROSSED AND SELF-FERTILISED PLANTS. 69 Crossed and self-fertilised Plants of the Sixth Generat-ion.-Seeds from plants of the fifth generation crossed and self-fertilised in the usual manner weJ~e sown on opposite sides of several pots. On the self-fertilised side every single plant belonged to the tall white variety. On the crossed side some plants belonged to this variety, but the greater number approached in character to the old and shorter kinds with smaller yellowish flowers blotched with coppery brown. When the plants on both sides were from 2 to 3 inches in height they were equal, but when fully grown the self-fertilised were decidedly the tallest and finest plants, but, from want of time, they were not actually measured. In half the pots the first plant which flowered was a self-fertilised one, and in the other half a crossed one. And now another remarkable change was clearly perceived, namely, that the self-fertilised plants had become more self-fertile than the crossed. The pots were all put under a net to exclude insects, and the crossed plants produced spontaneously only fifty-five capsules, whilst the self-fertilised plants produced eighty-one capsules, or as 100 to 147. The seeds from nine capsules of both lots were placed in separate watch-glasses for comparison, and the self-fertilised appeared rather the more numerous. Besides these spontaneously self-fertilised capsules, twenty flowers on the crossed plants again crossed yielded sixteen capsules; twenty-five flowers on the self-fertilised plants again self-fertilised yielded seventeen capsules, and this is a larger proportional number of • capsules than was produced by the self-fertilised flowers on the self-fertilised plants in the previous generations. The contents of ten capsules of both these lots were compared in separate watch-glasses, and the seeds from the self-fer-tilised appeared decidedly more numerous than those from the crossed plants. Grossed and self-fertilised Plants qf the Seventh Generation.Crossed and self-fertilised seeds from the crossed and self-fertilised plants of the sixth gener·ation were sown in the usual manner on opposite sides of three pots, and the seedlings were well and equally thinned. Every one of the self-fertilised plants (and many were raised) in thisJ as well as in the eighth and ninth generations, belonged to the tall white variety. Their uniformity of character, in comparison with the seedlings first raised from the purchased seed, was quite remarkable. On the other hand, the crossed plants differed much in the tints of their flowers, but not, I think, to so great a degree as those first raised. I determined this time to measure the plants on both sides |