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Show 212 ILLEGITIMATE OFFSPRING OF CHAP. v. two distinct species, for the seeds in this latter case are often incapable of germination. The following observations relate to the nature of the forms which appear among the legitimate seedlings of Oxalis Vald,iviana. Hildebrand raised, as described in the paper just referred to, 211 seedlings from all six legitimate unions, and the three forms appeared among the offspring from each union. For instance, long-styled plants were legitimately fertilised with pollen.from the longest stamens of the mid-styled form, and the seedlings consisted of 15 long-styled, lH mid-styled, and 6 short-styled. V\T e here see that a few short-styled plants were produced, though neither parent was short-styled; and so it was with the other legitimate unions. Out of the above 211 seedlings, 173 belonged· to the same two forn1s as their parents, and only 38 belonged to the third form distinct from either parent. In the case of 0. RegnelU, the result, as observed by Hildebrand, was nearly the same, but more striking: all the offspring from four of the legitimate unions consisted of the two parent-forms, whilst amongst the seedlings from the other two legitimate unions the third form appeared. Thus, of the 43 seedlings from the six legitimate unions, 35 belonged to the same two forms as their parents, and only 8 to the third form. Fritz M tiller also raised in Brazil seedlings from long-styled plants of 0. Regnelli legitimately fertilised with pollen from the longest stamens of the mid-styled form, and all these belonged to the two parentforms.* Lastly, seedlings were raised by me from long-styled plants of 0. speciosa legitimately fertilised by the short-styled form, and from the latter reciprocally fertilised by the longstyled; and these consisted of 33 long-styled and 26 shortstyled plants, with not one mid-styled form. There can, therefore, be no doubt that the legitimate offspring from any two forms of Oxalis tend to belong to the same two forms as their parents; but that a few seedlings belonging to the third form occasionally make their appearance ; and this latter fact, as Hildebrand remarks, may be attributed to atavism, as some of their progenitors will almost certainly have belonged to the third form. When, however, any one form of Oxalis is fertilised illegiti- * 'Jenaische Zeitschrift,' &c. Band vi. 1871, p. 75. CHAP. V. HETEROSTYLED DIMORPHIC PLANTS. 213 · mately ~ith ~ollen from. the same form, the seedlings appear to belong Invariably to this form. Thus Hildebrand states* that long-styled plants of 0. 1·osea growing by themselves have been propagated in Germany year after year by seed, and have always produc~d long-styled plants. Again, 17 seedlings were raised from mid-styled plants of 0. hedysaroides growin()' by themselves and th~se were all mid-styled. So that the f~rms of Oxalis' when illegitimately fertilised wth their own pollen, behave lik~ the long-styled form of Lythrum salicaria, which when thus fertilised always produced with me long-styled offspring. PRIMULA. PRIMULA SINENSIS. I . raised during February 1862, fro1n some longstyled plants illegitimately fertilised with pollen fron1 the same form, twenty-seven seedlings. These were all long-sty led. They proved fully fertile or even fertile in excess; for ten flowers, fertilised with pollen from other plants of the same lot, yielded nine capsule~, cont~ining on an average 39 · 75 seeds, with a maximum In one capsule of 66 seeds. Four other flowers legitimately crossed with pollen from a legitimate plant, and four flowers on the latter crossed with pollen from the illegitimate seedlings, yielded seven capsules with an average of 53 seeds, with a maximum of 72. I must here state that I have found some difficulty in estimating the normal standard of fertility for the several unions of this species, as the results differ much during successive years, and the seeds vary so greatly in size that it is hard to . * 'Ueber uen Trimorphismus ln ~er Gattu11g Oxalis: MonatsberlChte der Akad. der Wissen. zu Berlin,' 21st June 1866, p. 373; and • Bot. Zeitung,' 1871, p. 435. |