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Show 134 DIANTHUS CARYOPHYLL US. CHAP. IV. plant; and these produced twenty~two ca?sules, containing onarn average 35·95 seeds, with a max1mum In one of 61 seeds. VVe thns see, judging by the number of seeds per cap~ule, that tho crossed plants again crossed wore more productive than the self-fertilised again self-fertiUsed, in the ratio of 100 to 65. Both the crossed and self-fertilised plants, from having grown much crowded in the two beds, produced less fino capsules and fewer seeds than did their parents. Crossed and selj-jtrtilised Plants of the Second Generation.-1 1 he crossed and self-fertilised seeds from the crossed and self-fertilised plants of the last generation were sown on opposite sides of two pots; but the seedlings were not thinned enough, so that both lots grew very irregularly, and most of the self-fertilised plants after a time died from being smothered. My measurements wore, therefore, very incomplete. From the first the eros eel seedlings appeared the finest, and when they were on an average, by estin1ation, 5 inches high, the self·fertilised plants were only 4 inches. In both pots the crossed plants flowered fir. t. Tho two tallest flower-stems on the crossed plants in the two pots were 17 and 16! inches in height ; and the two tallest flowot·-stems on tho self-fertilised plants 10! and 9 inches; , o that their heights were as 100 to 58. But this ratio, deduced from only two pairs, obviously is not in tho least trustworthy, and would not have been given had it not been otherwise sur ported. I state in my notes that the crossed plants were very much more luxuriant than their opponents, and seemed to bo twice as bulky. This latter estimate may be believed from tbo ascertained weights of the two lots in the next generation. Some flowers on these crossed plants were again crossed with pollen froni another plant of the E=ame lot, and some flowers on tbe self- · fertilised plants again self-fertilised; and from tho seeds thus obtaineGl the plants of the next generation wore raised. Crossed and stlf-fertilised Plants of the ThiTd Generation.-Tho · seeds just alluded to were allowed to germinate on bare sand, and were planted in pairs on the opposite sides of four pots. When tbe seedlings were in full flower, tho tallest stem on 0ach plant was measured to the base of tbe calyx. ,:rho measurements are given in the following table (XI.J VI.). In Pot I. tho crossed and self-fertilised plants flowered at the same time; but in the other three pots the crossed flowered first. These latter plants also continued flowering much later in tho autumn than the self-fertilised. CHAP. IV. CROSSED AND SELF-FERTILISED PLANTS. 135 TABLE XLVI. Dz'anthus caryophyllus (Th. _7 G . ZrLU eneratwn) No. ofPot. I Crossed Plants. I Se~-fertilised Plants. i - - - - - -- lnclw::. I. 2Sg Inches. 30 27~ 26 -- - -I II. 29 - I 29~ 30~ ' 27 ~ I III. 28d 31~ 23~ 24g - ~- IV. 27 30 33~ 25 --- -- - Total in inche ·. 227·1.'3 225•75 The average height of the . h inches, and of the ei ·ht ' eig .t. crossed plants is here 28.39 So that th g . ~elf-fertihsed 28 · 21 ; or as 100 t go ere was no difference in h . h o v. but in general vigour and 1 . eig t worth speaking of. d .ffi uxunance ther . ' I erence, as shown by th . . 1 e was an astomshinO' h d mr wmg 1ts Aft th 5 a been gathered tile · ht · er o seed-capsules 1 ' mg crossed and th · 1 Pants were cut down .... nd . h d e mg 1t self-fertilised "~ weig e · tbe £ . ounces, and tho latter only 21 ' ormer weJghecl 43 These plants wore all 1 t oundces; or as 100 to 49. h . • mp un er a net th w ICh they produced m t h ' so u.t the capsules fertilised. The ei'ght us d ave been all spontaneously self-crosse plants . d d capsules, of which onl t I pro uce twenty-one such 8·5 per capsule On ;h we ve contained any seed, averaging plants produced. 1 e other hand, the eight self-fertilised'- . no ess than th · t · exammed twenty-five and . n y-six capsules, of which I contained seeds a ' . , With the exception of three ''11 , veraging 10 · 63 d ' ·~ proportional number f see s per capsule. Thus the of crossed oriO'in to tl o seeds per cap ule produced by the plants origin (both l~ts bei;~se produced by tho plants of solf-fertilisecl to 125. This an I o spontaneously self-fertilised) was as 100 self-fer~ilised pla~:a::i:osult. is probably due to some of the and stigmas more I g vaned o as to rna ture their pollen th e speC.ie s . and nhe ar Y at the s arne t I·m e than I·S proper to ' we ave already seen that some plants in the |