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Show 78 MIMUL US LUTE US. Hero tbo averaO'e height of tho twenty-two crossed plants is 16 · 85, and that of the twenty-two self-fertilised plants 16 · 07; or as 100 to 95. But if four of the plants in Pot VII., which are 1nuch shorter than any of the others, are struck ont (and this would be tho fairest plan), the twenty-one crossocl aro to the nineteen self-fertilised plants in height as 100 to 100 · G--that is, aro equal. All the plants, .except the crowded ones in Pot VIII.; after hoing measured wore cut down, and the oightoon crossed plants weighed 10 oz., whilst the same number of self-fertilised plants weighed 10! oz., or as 100 to 102 · 5; but if the dwarfed plants in Pot VII. had been excluded, the self-fertilised would have exceeded the crossed in weight in a bighor ratio. In all the previous experiments in which seedlings were rai.·ed from a cross between distinct plants, and were put jnto competition with self-fertilised plants, the former generally flo,vorec1 first ; but in tho present case, in seven out of the ojght pots a self-fertilised plant flowered before a crossed one on the opposi to side. Considering all the evidence with respect to the plants in Table XXII., a cross between two flowers on the same plant seems to give no advantage to the offRpring thus produced, the self-fertilised plants being in weight superior. But this conclusion cannot be absolutely trusted, owing to tho 1neasuremonts given in Table XXI., though these latter, from the cause already assigned, are very 1nuch less trustworthy than the present ones. Sum.mary of Observations on Mimulus luteus.-In the three first generations of crossed and self-fertilised plants, the tallest plants alone on each side of the several pots were measured ; and the average height of the ten crossed to that of the ten self-fertilised plants was as 100 to 64. The crossed were also much more fertile than the self-fertilisecl, and so much more vigorous that they exceeded them in height, even when sown on the opposite side of the same pot after an interval of four days. The same superiority was likewise shown in a remarkable manner when both kinds of seeds were sown on the opposite sides of a pot with very poor earth full of the roots of another plant. CHAP. HI. SUMMARY OF OBSERVATIONS 79 In one . ins · t ance crossed and . . · grown In rich soil cl se~f-fertlhsecl seedlin . h an not put t gs, eac other, attained to In o competition with COine to the fourth gener:~io:qual height. When we plants taken too·ether ex cl the two tallest crossed ~llest self-fertilised pl· ctee ed by only a little the two Its crosse d opponenta-n s, . .a nd one of th e latter beat occurred in the p : a cucumstance which had t rev1ous gen . t' c no self.- fertilised plan t consi. stede ioaf Ions. This victo n.·o us van. et.y ' wh I' c-h grew taller tha a new wh 't · fi I e- owered vaneties. From th fl . . n the old yello . h fertile h e Ist It seemed to b . Wis . ' w en self-fertilised th e Iather more In the succeed.i ng self-fe' rtilaisne the old v~ne· tie· s, and more and Jnore self-fertile I d g.enerations became self-fertilised plants of th: n .the Sixth generation-the crossed plants produced I::anety ~om pared with the of 147 to 100, both lots bp~ules In tho proportion :hemselves spontaneously Iemfh allowed to fertilise wenty flowers on one ~f n e seventh generation self-fertilised yielded no 1 these P!ants artificially capsules ! ess than nineteen ver .!! Thi . y une !f s vanety transmitt l .t all the succeeding sel~~f~r:il~:~a.cters so_ faithfully . l.e last or ninth, that all the e generations, up to t ihaised presented a complete m~i'ny ~lants which were .u s o: ffie n·n g a remarkabl un11.o rm I t y of character. raised from th e contrast with the se dl' ' retained to the kurchased seeds. yet this e ~ngs yellow fl e st a latent tendenc vanety fertilised owers; ~or when a plant of th~ t? produce yell generatiOn was crossed 'th eighth self- . ow-flowered plant of th o:l pollen from a Single seedling . bore yello fi e elsea stock, every .a t le as t I·n the colour owf 'to wfeir s . A S·i m·i lar variety Namo ong~":s t th 1 s owers 1 ' • e crossed plants of th '.a so appeared attention was at first 'd ~ thu·d generation. pal to It' and I 1r now not |