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Show 276 SUMMARY OF MEASUREMENTS. CHAP .. VII. (7.) Viscar/a oculata.-The average h ight oftho fifteen intercrossed plants to that of the fifteen self-fertilised plant8 was only ap, 100 to 97; but the former produced many more capsules than tho latter, in the ratio of 100 to 77. l\1oreover, tho flowers on the parent-plants which were crossecl and self-fortili. ed, yielded seeds on one occasion in the proportion of 100 to 38, and on n second occasion in the proportion of 100 to 58. 8o that there can be no doubt about the beneficial effects of a cross, a]t]wugh tho mean height of the crossed plants was only throe per cent. above that of the self-fertilised plants. (tl.) Speculari;(JJ sz;ecnl11m.-Only tho four tallest of tho crossed and the four tallest of tho self-fertilised plants, growiDg in fom pots, were measured ; and the former wore to tho latter in height as 100 to 98. In all four pots a cro ·sod plant fiowerecl before any one of the self-fertilised plr.nts, and this is usually a safe indication of some real superiority in the cro , ed plants. The flowers on the parent-plants which wore crossed with pollen from another plant yielded SC'od · compared with the self-fertiliBed fiowors in tho ratio of 100 to 72. We may therefore draw the same conclusion as in tho last case with respect to a cross being decidedly beneficial. (9.) JJora,go officinalcis.-Only four crossed ancl four selffertilised plants wore raised and measured, and the former were to tho latter in height as 100 to 102. So small a numbor.of measurements ought never to be trnRtod; and in tho pr~c;ont mstance tho advantage of the self-fertilised over the crosRocl plants depended almost entirely on one of the self-fertilised plants having grown to an unusual height. All four crossed pbnts flowered before their solf-ft-rtiliscd opponents. Tho crossfertilised flowers on tho parent-plants in comparison with tho self-fertilised flowers yielded seeds in tho proportion of 100 to GO. So that here again we may draw the same conclusion as in the two last cases. (10.) Passiflora gracilis.-Only two crossed and t'vo f'el.ffertilised plants wore rai ed; awl tho former were to the htttor m height as 100 to 104. On tbo other hand, fruits from the cro ·sfertilisedflowers on the parent-plants contained seeds in number, compared with those from the self-fcrtilisetl flow ers, in the pro-portion of 100 to ~5. t (11.) Phaseolus multijlo?·us.-Tho five crossed plants were 0 the five self-fertilised in height as 100 to 9G. Althongh the crossed plants were thus only four per cent. taller than the CHAP. VII. TABLE A. 277 self-fertilised, they flowered in both pots before them. It is therefore probable that they had some real advantage over tho self-fertilised plants. (12.) Adonis cestivalis.-The four crossed plants were almost exactly equal in height to 1,he four self-fertilised plants, but as so few plants were measured, and as these wore all "miserably unhealthy,'' nothing can be inferred with safety with respect to their relat~ve heights. (13.) Bartonia atwea.-The eight crossed plants were to the eight self-fertilised in height as 100 to 107. This number of plants, considering tho care with which they were raised and compared, ought to have given a trustworthy result. But from some unknown cause they grew very unequally, and they became so unhealthy that only three of the crossed and three of the self-fertilised plants set any seeds, and these few jn number. Under those circumstances tho mean height of.neithor lot can be trusted, and the experiment is valueless. The crossfertilised flowers on the parent-plants yielded rather mor8 seeds than the self-fertilised flowers. (14.) 1'hunber,qia alata.-The six crossed plants were to the six self-fertilised in height as 100 to 108. Here the self-fertilised plants scorn to have a decided advantage; but both lots grew unequally, some of tho plants in both being more tban twice as tall as others. The parent-plants also were in an odd semisterile condition. Under these circumstances the superiority of the self-fertilised plants cannot be fully trusted. (15.) Noluna prostrata.-The five crossed plants were to the five self-fertilised in height as 100 to 105; so that the latter seem here to have a small but decided advantage. On the other hand, the flowers on the parent-plants which were .cross-fertilised produced very many more capsules than the self-fertilised fiowers, in the ratio of 100 to 21; and tho seeds which the former coutained were heavier than an equal number from the self-fertilised capsules in the ratio of 100 to 82. (16.) IHbiscus ajl"l'canus.-Only four pairs wore raised, and the crossed were to the self-fertilised in height as 100 to 109. Excepting that too few plants wore measured, I know of nothing else to cause distrust jn the result. The cross-fertilised flowers on the parent-plants wore, on the other hand, rather more productive than the self-fertilised flowers. (17.) Apium pet}'()selinum.-A few plants (number not recorded) derived from flowers Lelievecl to have boon crossed by |