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Show 224 PRIMULA VERIS. 0IJAP. VI. TABLE XCIV. P rimula veris (equal-styled, red-flowered variety). Crossed Plants. Self-fertilised Plants. No. of Pvt. Height of tallest Flower-stem in inches. No. uf Flowerstems. Height of No. of good tallc 't Capsules. Flower- tom in inches. No. of Flower No. of good st ems.- Capsules. - ---'--·'--- - 1 ----- ----- --- -1. 1 10= \ 14 1 163 II. · 12 Several, not counted. 6 6 5 2 0 The average height of the three tallest flower-stems on the crossed plants is 8 · 66 inches, and that of the three on the self-fertilised plants 7 · 33 inches ; or as 100 to 85. All the crossed plants together produced thirty-throe flowerstems, whilst the self-fertilised bore only thirteen. The number of the capsules were counted only on the plants iri Pots I. and III., for the self-fertilised plants in Pot II. produced none; therefore those on the crossed pla:rats on the opposite side were not counted. Capsules not containing any good seeds were rejected. The crossed plants in the above two pots produced 206, and the self-fertilised in the same pots only 32 capsules; or as 100 to 15. Judging from the previous generations, the extreme unproductiveness of the self-fertilised plants in this experiment was wholly due to their having been subjected to unfavourable conditions, and to severo competition with the crossed plants; for had they grown separately in good soil, it is almost certain that they would have produced a largo number of capsules. The seeds were counted in twenty capsules from the crossed plants, and they averaged 24 · 75; whHst in twenty capsules from the self-fertilised plants the average was 17 · 65 ; or as 100 to 71. Moreover, the seeds from tho self-fertilised plants were not nearly so fine as those from the crossed plants. If we consider together the number of capsules produced and the average number of contained seeds, tho fertility of the crossed plants to tho self-fertilised plants was as 100 to 11. CHAP. VI. PRIMULA SINENSIS. 225 We thus see what a great effect, as far as fertility is concerned was produced by a cross between the two varieties, which had been long exposed to different conditions, in comparison with self-fertilisation; the fertilisation having been in both cases of the legitimate order. PRIMULA SINENSIS. . As the Chinese prim:os~ is ~ heterostyled or dimorphic plant, hke the common cowslip, It ;might have been expected that the flowers of both forms when illegitimately fertilised with their own pollen or with that from flowers on another plant of the same form, would have yielded less seed than the legitimately crossed flowers; and that the seedlings raised from illegitimately self-fertilised seeds would have been somewhat dwarfed and less fertile, in comparison with the seedlings from legitimately crossed seeds. This holds good in relation to the fer~ ility of the flowers; but to my surprise there was no difference m growth between the offspring from a legitimate union between two distinct plants, and from an illegitimate union whether between the flowers on the same plant, or.between distinct plants of the same form. But I have shown, in the paper before referred to, that in England this plant is in an abnormal condition such as, judging from analogous cases, would tend to render ~ cross between two individuals of no benefit to the offspring. Our plants have been commonly raised from self-fertilised see.ds; and the seedlings have generally been subjected to nearly umform conditions in pots in greenhouses. Moreover, many of the plants are now varying and changing their character so as to become i~ a greater or less degree equal-styled, and i~ consequence highly self~fertile. From the analogy of P. ver is there can hardly be a doubt that if a plant of P. sinensis could have h~en procured direct from China, and if it bad been crossed With one of our English varieties, the offspring would have shown wonde~ful superiority in height and fertility (though probably not In the beauty of their flowers) over our ordinary plants. My first experiment consisted in fertilising many flowers on long-styled and short-styled plants with their own pollen, and other flowers on the same plants with pollen taken from distinct ~lants belonging to the same form· so that all the unions were Illegitimate. There was no unifo~m and marked difference in Q |