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Show 172 SCABIOSA ATRO-PURPUREA. CHAP. v. XVIII UMBELLIFER.lE.-APIUM PETROSELINUM. · tcrandrous and can hardly fail to be h U b u· ferre are pro ' T o m c 1 'l' d b · tho· many fh.o s and sman Hymenoptera which cross-fertJ1Se ~ A 1 nt of tho common parsley was covered visit th~:o::~s. it ap:a~cntly produced as many and ~s. ~no l>y a n ' lf f ·t'lisod fruits or seeds as tho nilJommg snontancously so - or 1 · ·t ,..,~ b L' lants Tho flowers on the latter wore VI 'I ,O\ t y so uncove:cd pt . th. t thcv must have received pollen from one many msoc s a ,; 1 ft d b t another. Some of theso two lots of scod~ wcrdo bo c .ontbsan t'l ~s nearly all t h c so lf.- fo rt 1.11·'R od seeds gcrmmato OlOie · · c o 1011 ' f , d to throw all away. Tho roma1n1ng sccc s so that I was orco tho opposite sides of four pots. At first the woro then sown on 1 · t f tl pots self-fertilised seedlings were a little tal er .1n mos o JO than tho naturally crossed seedlings, and t~Is no donbt wu,s dt~c to the self-fertilised seods having germmatod. fir~t. But m h t 11 the Plu,nts were so equal that 1t dtd not scorn t e au u mn a t th T worth while to moasuro them. In two of tho. po s e~ "oro absolutely equal; in a third, if there was any d1ffcronco, It _was in fa.vonr of the crossed plants, and in a somewhat plam_cr . the fourth pot But neither side had any substantJal manner 1n · . h · ht th be said advantage over tho othor; so that 1n mg oy may - to be as 100 to 100. XIX. DIPSAOE.lE.-SOABIOSA ATRO-PURPUREA. The flowers, which are proterandrous, wore fertilised during TA.BLE LXV. Scabiosa (),tro-purp~trea. No. of Pot. Crossed Plants. Self- fertiUc;cd Plants. Inch es. Inches. I. II. III. - Total in inches. * H. Mi.illor, 'Defrnchtung-,' &r. p. 96. According to M. Mustcl (as stated. by Godron, ' De l'Es- 14 20 15 14 ~ -- 21 14 18~ 1;) - -- - --- 68·5 Gl·5 - , , t . . 58 18J-9), varieties pece, om. n. P· ' . . each of the carrot growmg neai otbor readily intoroross. CHAP. v. LACTUCA SATIVA. 173 th~ unfavourable season of 1~67J so that I got few seeds, especially from the self-fertilised heads, which were extTemely sterile. The crossed and self-fertilised plants Taiscd fTom these seeds wore measured before they were in full flowcT, as in the preceding ta hle. The four crossed plants averaged 17 ·12, and the four self-fertilised 15 · 37 inches in height; or as lCO to 90. One of the selffertilised plants in Pot III. was killed by an accident, and its fellow pulled up; so that when they Wt!re again measured to the summits of their flowers, there wore only three on each side; the crossed now averaged in height 32 · ~3, and the self-fertilised 30 ·16 inches; or ~s 100 to 92. XX. COMPOSITlE.-LACTUOA SATIVA. ·Three plants of Lettuce* (Great London Cos var.) grew close together in my garden; one was covered by a net, and produced self-fertilised seeds, the other two were allowed to be naturally crossed by insects; but the season (1867) was unfavourable, and I did not obtain many seeds. Only one crossed and one selffertilised plant were raised in Pot I., and their measurements are given in the following table (LXVI.). The flowers on this one self-fertilised plant were again self-fertilised under a net, not with pol~en from the same floret, but fr0m other florets on tbe same head. The flowers on the two crossed plants were left to be crussed by insects, but the proctss was aided by sowe pollen being occasionally transported by me from plant to plant. These two lots of seeds, after germinating on sand, were planted in pairs on the opposite sitles of Pots II. and III., which were at first kept in the gTeenhouse and then turned out of doors. The plants were measured when in full flower. The following table, therefore, includes plants belonging to two generations. When the seedlings of the two lots were only f> or 6 inches in height they were equal. In Pot III. one of tht:J self:.fertilised plants died before flowering, as has occurred in so many other cases. * TL.e Corupositro arc welladapt~ d for cro::;s-fertilisation, but a nursc1 yman on whom I ca.u rely, toltl me tl1at he had been iu the h<tLit of sowing several kind.s of lottucd near too·ethcr for the sake of seed, und Lu.J never obsened that they became cros::H:d. lt is very improbable that all the varieties which wme thus cultivated ncar together flowered at diflere,,t times; but two which I selectl-d by hazard. 11nd. sowe1l near each other Jid. not tlowcr at the same time ; and my trial failed. |