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Show 38 JPOMCEA. PURPUREA. CHAP. II. Each of these nine crossed plants is higher than ~ts opponen~: though in one case only by three-quarters of an Inch. '!~en h · ht · u3 · 94 inches and that of the self-fertihsccl average eig IS 0 ' . plants 68 ·25, or as 100 to 81. These plants, aft~r growing. to their full height, became very unhealthy and Infested with aphides, just when the seeds were setting,. so that m~ny of ~he 1 f ·1 d and nothing can be said on thmr relative capsu es ai e , fertility. . . C'rossed and self-fertilised Plarnts of the E~~hth Generatw~.-As just stated, the plants of the last generatwn, from wl1.1Ch the present ones were raised, were very unhealthy and th01r seeds of unusually small size; and this probabl! a~counts for the two lots behaving differently to what they did In any of the. ~revious or succeeding generations. :Many of the self- fertilised seeds germinated before the crossed ones, and these were of course rejected. When the crossed seedlings in Table IX. had grown to a height of between 1 an~. 2 feet, they were all, or almost all, shorter than their self-fertilised opponents, but ~ere not then measured. When they had acquired an average hCJ ght of 32· 28 inches that of the self-fertilised plants was 40 · 68, or as 100 to 122. Moreover, every one of the sclf-fertihscd plants, with a single exception, exceeded its crossed opponent. :Vhen, however the crossed plants had grown to an average hmght of 77" ·56 in~hes, they just exceeded (viz., by · 7 of an inch) the average height of the self-fertilised plants; but two of the latter were still taller than their crossed opponents. I was so much astonished at this whole case, that I tied string to the summits of the rods ; the plants being thus allowed to continue c]jmbing upwards. When their growth was complete they were untwined, stretched straight, and measured. The crossed plants had now almost regain~d their accustomed superiority, as may be seen in Table IX. The average height of the eight crossed plants is here 113 · 25 inches, and that of the self-fertilised plants ~6 · 65, or as 100 to 85. Nevertheless two of the self-f rtilised plants, as ma.y be seen in the table, were still higher than their crossed opponents. The latter manifestly had much thicker stems and many more lateral branches, and looked altogether more vigorous than the self-fertilised plants, and generally flowered before them. The earlier flowers produced by these self-fertilised plants did not set any capsules, and their anthers contained only a small amount of pollen; but to this subject I shall return. Nevcrthe- CHAP. II. CROSSED AND SELF-FERTILISED PLANTS. 39 less capsules produced by two other self-fertilised plants of th same lot, not i~cluded in Table IX., which had been highl; favoured by being grown in separate pots, contained the large average number of 5 ·1 seeds per capsule. TABLE IX. ( E1:gldh Generation.) No. of Pot. I Crossed Plants. Self-fertilised Plants. ---- -- I. Inches. Inches. 111 H 96 127 54 130~ 93~ ---- -- -- -- II. 97 g 94 s9 a 125H III. 103~ 115~ 1ooH 848 147 ~ 109 ~ Total inches. 908. 2,) 773•25 Grossed and sel.(-fertilised Plants of the Nt'nth Gerteration.The plants .of this generation were I'aised in the same manner as before, With the I'esult shown in Table X. :- The fourteen crossed plants average in height 81· 39 inches and the fou~~een self-fertilised plants ti4 · 07, or as 100 to 79. One self-f~rtihs~d plant in Pot III. exceeded,' and one in Pot IV. equalled In ~mght,. its ~~ponent. The self-fertilised plants showed no ~1gn o~ Inhel'l ting the precocious growth of their parents; this having been due, as it would appear, to the abnormal state of the seeds from the unhealthiness of th · parents. The fourteen self-fertilised plants yielded only£ e;r spontaneously self-fertilised capsules, to which must be ad~:~ seven, the product of ten flowers artificially self-fertilised On the other hand, the fourteen crossed plants yielded 152 ~p _ taneously self-fertilised capsules; but thirty-six flowers on th on plants were crossed (yielding thirty-three capsules) and these flowers would probably have produced about thirty spon~s~ neously self-fertilised capsules. Therefore an equal n b a of the CI'?ssed and self-fertilised plants would have pro~~ e~ capsules In the proportion of about 182 to 47 or as 100 to 2e~ t~other p~enomenon was well pronounced in' this generation. u I believe had occurred previously to a slight extent |