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Show 136 DIANTHUS CARYOPHYLL US. C IIAI). IV. first experiment differed from the oth ers in bein g slightly more self-fertile. The E.ff'ects of a Cross un:t.h a f resh ..Stoclc.-Twenty flowers on the self-fertilised plants of the last or third generation, in Table XLVI., were fertilised with their own pollen, but t al on from other flowers on the f:ame plants. These produced fifteen capsules, which contained (omitting two with only throe and six seeds) on an average 47 · 2:1 seeds, with a maximum of seventy in one. The self-fertilised capsules fron1 the self-fertilised plants of the first generation yielded the much lower average of 35 · 95 seeds; but as these latter plants grew extremely crowded, nothing can. be inferred with respect to this difference in their self-fertility. The seedlings raised from tho above seeds constitute tho plants of the fourth self-fertilised generation in the following table (XLVII.). 'l1welve flowers on the same plants of tho third self-fertilised generation, in Table XLVI., were crossed with pollen from the crossed plants in the ~arne table. Those cross.ed plants had been intercrossed for the three previous generations ; and many of them, no doubt, were more or less closely int er-related, but not. so closely as in some of the experi1nents with other species; for several carnation plants had been raised and cro sed in the earlier generations. They were not related, or only in a distant degree, to the self-fertilised plants. The parents of both the self-fertilised and crossed plants had been subjected to as nearly as possible the same conditions during tho three previous generat- ions. The above twelve flowers produced ten capsules, containing on an average 48 · 66 seeds, with a maximum in one of seventy-two seeds. The plants raised from these seeds may be called the intercrol'sed. Lastly, twelve flowers on the same self-fertilised plants of the third generation were crossed with pollen from plants which had been raised from seeds purchased in London. It is almost certain that the plants which produced these seeds had grown under very different conditions to those to which my selffertilised and crossed plants had been subjected; and they were in no degree related. The above twelve flowers thus crossed all produced capsules, but these contained tho low average of 37 ·41 seeds per capsule, with a maximum in one of Edxty-four seeds. It is surprising that this cross with a fresh stock did not give a 1nuch higher average number of seeds; for, as we shall immediately see, the plants raised from these seeds, which may CHAP. IV. n \YITH A FRE, II TO K. 137 be called the L ondon-cro ' 1' b n fit 1 O'r cn t1y by the ·rosA, both jn growth and fertility. The aboYe three lot of d w r allowed t . bare sand. l\I( ny of th L n l n- ro d 0' • . o t ~r~mato on others, and were rej ct d . and many of thic~I;: e efodrc] the than tho e of th ot her two lot. The cod ft ·otih·crosse ~tor t· 1 t d · · a CI u. germma-mg were p an e ln t n pot ' made tripartite by sup~rficial TABLE XL VII. Diwdhu c•1ryophy1lus. I London-cros ~fd I ., No. of Pot. Plant lntercro ed Plants. • t- If-fertilised Plants. ---- -- --- Inche •. I. Inches. Inches. _I 39' 25 1 29 ~ 301 2 1 ~ + II. ,--3g~ -- -- 22 -'l + - -- -- III. I 2 ~ 30i + 23~ -- IY. 3.:.! 35.- I 30 1- - k 32 24~ - - - Y. 2 0 __ / 34~ + 1- 24§ + YI. 32 5 24~ 31 ! 30~ 1- 26 24a -- -- - YII. 41 2 9 ~ 3-H 27 ~ 1- 2 6 ~ 27 .I YIII. 3-H - 29 2G ~ 2 .') 0 1- b + IX. I --- -- 25~ I - 0 2 8~ + 1- I + 0 X. -- 3 2 3 2~3 391 1- ~ !l I + 0 - Total in inche • - 525 '10 420 ·00 2G5 ·50 '-- |