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Show CALIFORNICA. CHAP. IV. ESCHSCHOLTZIA . 114 'f there had been nme-with their weigh t cal.c u. latde d thase 1 nineteen sol f -f or tT d II e plants ( . h d 18.2 ounces, an D for tho weight, of the teen) wmg e We bave there ore l)lants, 21· 5 ouncesthe following ratios :- three lots of plants lf fertilised plants, as 100 to 118 1. h crossed to these - , d plantR as 100 to 100 The Eng IS - t the intercros e , ' 0 t 118 The English-crossed ~ lf-fertmsed plants, as 10 o . The intercrossed to t e se . hel· o·llt tho solf-fortili ·ed . . . ·ht as m b ' . d We tb us sede ecthidaetd ma dwvmang tag' e over the English-crossed an plants had a . r not in a intercrossed_plants. eds of the three kinds, whetlJe~ l~el rows in The remammg se in three long para . ·t te of germination, were s.own in tho self-fertilised , cedl~ngs s a en ground; and here aga 2 and 3 inches tho scecllmgs the op . . ht by between al height . The exceeded Ill beig h"ch v·Gre of nearly oqn d all 1·n the two other rows, w 1t t ~ throughout tho winter, an lf three rows were 1e f t u npro' tchc tehl'e exception of t wo of tbe se - the plants were killed, WI this little bit of evidence goes, so~c fertilised; so t~a~ as fn~a:~s were more hardy than any of t e f the self-fertilised P o d lants of either lot. . . 1 ts which were grown crosse p that the self-fertilised pan 116 t 100) and in We thus see erior in height (as . o , inter- :e~:~tn~~: f~~st:~~~) ::~d apparent~ei~~::d~~:s~r~n~~~ildren crossed plants derived from a CI~s:riority is here much more f the Brazilian stock. The s pd t =al with the plants of t~e o k d th n in the secon rl th crossed m strongly mar e_ ~-·h the self-fertilised were to ef t if we English stock, In w IC . far more remarkable ac - bei ht as 101 to 100. It IS a . lants with pollen from a g · · d the effects of crossmg P < • 1 bear In mm ~11mu us, Brassica, an0d9 fresh stock in the case~ .of Ipom~a~xceeded in height (as 1 Iberis-tbat the se1f-fertihsed plant 100) the offspring of the to 100) and in weight (as 118 Eto l·sh 'stock. the two stocks ' d b the 1 ng J ' •• Brazilian stock crosse y . d 1 different conditions. having been long subjected t? _wi e/the three Jots of plants w~ If we now turn to the ferhhty o mi e that in five ou~ o find a very different result. ~ may pro d was one of the Englls~- the nine pots t h e fi rs t P1 a n t wb. iCh flowereIf -fertilised P1a nt ·' 'a nd 1D crossed ; in four ?f the. pots;t ~t~~ a ;Zwer first ; so that ~~:~ not one did an mtercross: p ~n ect as in so many. o . latter plants were beaten In. t.hi~ res~ ws' of plants growmg Ill wayR. The three closely adJOining ro CHAP. IV. CROSS WITH A FRESH STOCK. 115 the open ground flowered profusely, and the flowers were incessantly visited by bees, and certainly thus intercrossed. The manner in which several plants in the previous experiments continued to be almost sterile as long as they were covered by a net, but set a multitude of capsules immediately that they were uncovered, proves how effectually the bees carry pollen from plant to plant. My gardener gathered, at three successive times, an equal number of ripe capsules from the plants of the three lots, until he bad collected forty-five from each Jot. It is not possible to judge from external appearance whether or not a capsule contains any good seeds; so that I opened all the capsules. Of the forty-five from the English-crossed plants, four were empty; of those from the intercrossed, five were empty; and of those from the self-fertilised, nine were empty. The Reeds were counted in twenty-one capsules taken by chance out of each lot, and the average num her of seeds in the capsules from the English-crossed plants was 67; from the intercrossed, 56; and from the self-fertilised, 48 ·52. It therefore follows that The forty-five capsules (the four empty ones inSeeds. cluded) from the English-crossed plants contained 2747 The forty-five capsules (the five empty ones in-cluded) from the intercrossed plants contained 2240 The forty-five capsules (the nine empty ones in-cluded) from the self-fertilised plants contained 1746·7 The reader sh~uld remember that these capsules are the product of cross-fertilisation, effected by the bees; and that the dHference in the number of the contained seeds must depend on the constitution of the plants ;-that is, on whether they were derived from a cross with a distinct stock, or from a cross between plants of the same stock, or from self-fertilisation. From the above facts we obtain the following ratios:- Number of seeds contained in an equal number of naturally fertilised capsul~s produced- By the English-crossed and self-fertilised plants, as 100 to 63 By the English-crossed and intercrossed plants, as 100 to 81 By the intercrossed and self-fertilised plants, as 100 to 78 But to have ascertained the productiveness of the three lots of Plants, it would have been necessary to know how many capsules were produced by the same number of plants. The I 2 |