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Show CHAP. II. IPOl\HEA PURPUREA. 48 tion. Thei·r relative heights are shown in the two following tables:- TABLE XIV - I Self-fertilised Plants Self-fertilised Plants of the Seventh Gene- of the Seventh Gene- No. of Pot. ration, Children of ration. Hero. - - Inches. 1- Inches. 89~ I. 74 60 61 55i 49 1- 82 92 II. 56 91H 74~ 38 - - Total inches. 447·25 375•50 L - .. . ·elf-fertilised children of Hero The average hejgh.t of the o~~h: ordinary self-fertilised plants . 74·54 inches, whilst that . . l 62·58 inches, or as 100 IoSf the correspon a·I ng oa eneratwn IS on y . to 84. TABLE XV. l I Self-fertilised Plants IntPrcrossed Plants of of the 8eventh Gene- the Seventh Gene- No. of Pot. ration, Children of ration. Hero. - -- 1- Inches. 1- Inches. III. 92 76~ IV. 87 89 87 § 86~ - Total inches. 266•75 252·50 I - . h three self-fertilised children ~f Here the average hmght. oft e he intercrossed pla~t~ IS Hero is 88.91 jnches, whilst that of t tl at the self-fertihsed 84 ·16 . or as 100 to 95. We thus see 1s of gi·owth of thei·r childre' n of Hero certam· 1 y I· n1 1 eri' t th.e pohweie rh t the self-ferti.h .s e d parents; for they greatly ~~~:~~s~~ pla~ts, and even exc~ed offsprin rr of the other self t ll of the correspondmg by a trifle the intercrossed plan s,-a generation. CHAP, II. DESCENDANTS OF HERO. 49 Several flowers on the self-fertilised children of Hero in Table XIV. were fertilised with pollen from the same :flower; and from the seeds thus produced, self-fertilised plants of the eighth generation (grand-children of Hero) were raised. Several othe1· flowers on the same plants were crossed with pollen from the other children of Hero. The seedlings raised from this cross may be considered as the offspring of the union of brothers and sisters. The result of the competition between these two sets of seedlings (namely self-fertilised and the offspring of brothers and sisters) is given in the following table:- TABLE XVI. Self-fertilised Grand- Grandchildren from a children of Hero, cross between the self- No. of Pot. from the Self-fertilised fertilised Children of Children. 1£ightb Hero. Eighth Gene- Generation, ration. --- Inches. 1ncbes. I. 86~ 95H 90~ 95i II. 96 85 77§ 93 III. 73 86~ 66 82~ 84~ 70~ IV. 88i 66~ 84 1 5~ 36~ 38 74 78~ v. 90fr 82~ 90~ 83~ Total inches. 1037•00 973•16 The average height of the thirteen self-fertilised grandchildren of Hero is 79 · 76 inches, and that of the grandchildren from a cross between the self-fertilised children is 7 4 · 85; Ol' as 100 to 94. But in Pot IV. one of the crossed plants grew only to a height of 15~ inches; and if this plant and its opponent are struck out, as would be the fairest plan, the average height of the crossed plants exceeds only by a fraction of an inch that of the self-ferti- E |