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Show 302 GYNO-DICECIOUS PLANTS. CHAP. VII. female plant were to those from the hermaphrodite as 100 to 56 in weight. If the relative weight of the seeds from an equal number of flower-heads from the two forms be compared, the ratio is as 100 for the female to 45 for the hermaphrodite form. Thymus vulgaris.-The common garden thyme resembles in almost every respect T. serpyllum. The saine slight differences between the stigmas of the two forms could be perceived. In the females the stamens are not generally quite so much reduced as in the same form of T. serpyllum. In some specimens sent me froin Mentone by Mr. Moggriclge, together with the accompanying sketches, the anthers of the Fig. 15. Hermaphrodite. Females. THYMUS VULGARIS (magnified). female, though small, were well formed, but they contained very little pollen, and not a single sound grain could be detected. Eighteen seecllino·s were raised f . b rom purchased seed, sown in the same small bed ; and these consisted of seven hermaphrodites and eleven females. They were left freely exposed to the visits of bees, and no doubt every female flower was fertilised ; for on placing under the microscope a large number of stigmas 'from female plants, CHAP. VII. GYNO-DICECIOUS PLANTS. 303 not one could be found to which pollen-grains of thyme did not adhere. The seeds were carefplly collected from the eleven female plants, and they weighed 98 · 7 grains ; and those from the seven hermaphrodites 36 · 5 grains. This gives for an equal number of plants the ratio of 100 to 58; and we here see, as in the last case, how n1uch more fertile the females are than the hennaphrodites. These two lots of seeds ·were sown separately in two adjoining beds, and the seedlings from both the hermaphrodite and female parent-plants consisted of both forms. Satureia hortensis.-Eleven seedlings were raised in separate pots in a hotbed and afterwards kept in the green-house. They .consisted of ten females and of a single hermaphrodite. Whether or not the conditions to which they had been subjected caused the great excess of females I do not know. In the females the pistil is rather longer than that of the hermaphrodite, and the stamens are mere rudiments, with minute colourless anthers destitute of pollen. The windows of the green-house were left open, and the flowers were incessantly visited by humble and hive bees. Alt~ough the ten females did not produce a single gra~n_ of pollen, yet they were all thoroughly well ~ertlhsed by the one hermaphrodite plant, and this Is an interesting fact. It should be added that no other plant of this species grew in my garden. The seeds were ?ollected from the finest female plant, and they weighed 78 grains; whilst those from the hermaphrodite, which was a rather Iaro·er plant than the. female, weighed only 33 · 2 grains ; 0 that is, in the rat1o of 100 to ~3. The female form, therefore, is very much more fertile than the hermaphrodite, as in the two I.ast. c.ases ; but t~e hermaphrodite was necessarily selfferhhsed, and th1s probably diminished its fertility. |