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Show 166 SAROTHAMNUS SCOPARIUS. CHAP. v. . 1 . h · O'ht. so that the former were more fertilised 1. 33 Inc l.es Jn eib ' 100 t 46 . h' has the latter, or as o . than twiCe as Ig a· . year (1869) the three crossed I the spring of the succee mg n . t I h d all grown to nearly a foot in height, and they plants Ill Po a' t; th e little self-fertilised plants so completely had smotherc :ad ~eand the third, only an inch and a half ~hat ~wo were ~ in' It should be remembered that these In height, ~as n ~ed~ed out in their pots,, so that they were plants had ce t't' This pot was now thrown subjected to very severe compe I wn. away. . 1 t · Pot II were all alive. One of the self- The six p an s In · f th ferti.h .s e d was an I.n c h and 'fL quarter taller than any one o . e d 1 t . but the other two self-fertilised plants were m a crosse pan sa'·t· I therefore resolved to leave these plants to very poor con I wn. f th stru '()'le toO'ether for some years. By the autum.n o . . e s~me ' ~argC18G9)bthe self-fertilised. plant which had _been viCton?us wYa s now b ea t en. The measurements are shown Ill. the followmg table:- TABLE LIX. Pot II.-Sarothamnus scoparius. Crossed Plants. Inches. 15~ 9R 8g \ Self-fertilised Plants. Inches. lok 3 2~ The same plantR were again measured in the autumn of the following year, 1870. TABLE LX. Pot II.-Sarothamnus scoparius. Crossed Plants. Self-fcrti Used Plants. -- Inche~. Inches. 26~ 14 ~ JG ~ 11 ~ 14 96s -- 56•75 35 ·50 - CHAP. v. ONONIS MINUTISSIMA. 167 The three crossed plants now averaged 18· 91, and the three self-fertilised 11 · 83 inches in height; or as 100 to 63. The three crossed plants in Pot I., as already shown, had beaten the threo self-fertilised plants so completely, that any comparison between them was superfluous. The winter of 1870-1871 was severe. In the spring the three crossed plants in Pot II. had not even the tips of their shoots in the least injured, whereas all three self-fertilised plants were killed half-way down to the ground; and this shows how much more tender they were. In consequence not one of these latter plants bore a single flower during the ensuing summer of 1871, whilst all three crossed plants flowered. 0NONIS MINUTISSIMA. This plant, of which seeds were sent me from North Italy, produces, besides the ordinary papilionaceous flowers, minute, imperfect, closed or cleistogene flowers, which can never be cross-fertilised, but are highly self-fertile. Some of the perfect flowers were crossed with pollen from a distinct plant, and six capsules thn ~ produced yielded on an average 3 · 66 seeds, with a maximum of five in one. Twelve perfect flowers were marked and allowed to fertilise themselves spontaneously under a net, and they yielded eight capsules, containing on an average 2 · 38 seeds, with a maximum of three seeds in one. So that the crossed and selffertilised capsules from the perfect flowers yielded seeds in the proportion of 100 to 65. Fifty-three capsules produced by the cleistogene flowers contained on an average 4·1 seeds, so that these were the most productive of all; and the seeds themselves looked finer even than those from the erossed perfect flowers. The seeds from the crossed perfect flowers and from the selffertilised cleistogene flowers were allowed to germinate on sand; but unfortunately only two pairs germinated at the same time. These were planted on the opposite sides of the same pot, which was kept in the greenhouse. In the summer of the ~arne year, when the seedlings were about 4! inches in height, the two lotR were equal. In the autumn of the following year (1868) the two crossed plants were of exactly the same height, viz., ll1f inches, and the two self-fertilised plants 12* and 7l inches; so that ono of the self-fertilised exceeded considerably in height all the others. By the autumn of 1869 the two crossed plants had acquired the |