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Show 94 ORIGANUM VULGARE. CHAP. III. It may be here seen that each of the six tallest crossed plants exceeds in height its self-fertilised opponent; the former averaged 27 · 85 inches, whilst the six tallest self-fertilised plants averaged 21·16 inches; or as 100 to 76. In all throe pots tho first plant which flowered was a crossed one. All the crossed plants together produced 409 flowers, whilst all the self-fertilised together produced only 232 flow~rs; or as 100 to 57. So that the crossed plants in this respect were far more productive than the self-fertilised. ORIGANUM VULGARE. This plant exists, according to H. Muller, under two forms; one hermaphrodite and strongly proterandrous, so that it is almost certain to be fertilised by pollen from another flower ; the other form is exclusively female, has a smaller corolla, and 1nust of course be fertilised by pollen from a distinct plant in order to yield any seeds. The plants on which I exporiInented were hermaphrodites; they had been cultivated for a long period as a pot-herb in my kitchen garden, and were, like so many long-cultivated plants, extremely sterile. As I felt doubtful about the specific name I sent specimens to Kew, and was assured that the species was 0. vul,gare. My plants formed one groat clump, and had evidently spread from a single root by stolons. In a strict sense, therefore, they all belonged to the same individual. My object in experimenting on them was, firstly, to ascertain whether crossing flowers borne by plants having distinct roots, but all derived asexually from the same individual, would be in any respect more advantageous than self-fertilisation; and, secondly, to raise for future trial seedlings which would constitute really distinct individuals. Several plants in the above clump were covered by a net, and about two dozen seeds (many of which, however, wore small and withered) were obtained from the flowers thus spontaneously self-fertilised. The remainder of the plants were loft uncovered and were incessantly . visited by bees, so that they were doubtless crossed by them. These exposed plants yielded rather more and finer seed (but still very few) than did the covered plants. The two lots of seeds thus obtained were sown on opposite sides of two pots ; the seedlings were carefully observed from their first growth to maturity, but they did not differ at any period in height or in vigour, the jmportance of which latter observation we shall presently see. When fully grown, the tallest crossed CHAP. III. ORIGANUM VULGARE plant in ono pot · 95 fertilised plant was a very 1i ttle taller tha exactly the rev on the opposite side and ~ tho tallest selfequal. a d crse occurred. So that' In the other pot two flo' n a cross of this kind did nc the two lots wore in fact wers on the o more go d th The plants . same plant of I pomCBa or M _o an crossing distu b d wore turned out of th Imulus. migh~ ~o:~oplanted in the open :r;::d P?ts without being self-fertilised an7 vrgorously. In the follo,;ln m·der that they hy a net. Ma~ ~Oinc of the quasi-crossed Ing summer all the pollen from a .Js!~~e~~a~~ the latter were ~;~~~d w~re covered by the bees. Thos . 'and others were le y me With seed than did thee q:asr-crossed plants produ!!dto be crossed to the action of thor~., mal ones in the great cl rather more plants were ar . . e ees. Many flowers o ump when left to fertilise th tliiCJally self-fertilised, and ~h the self-fertilised yielded altoo·e:;;-selves spontaneously undo~ t~rs wer·e allowed the product ~f a or. very few seeds. These tw ~ net, but they in the last case ~ross between distinct scedli~ . ots of seedsproduct of sclf-fer~tree~ plants multiplied b/:t ~nstead of as bare sand and I Isec flower·s- wore allow d t o ons, and the S·i des of t'w o l several e o aer · t c equal pairs wore 1 t o min a c on arc;e pot A P an ed on . plants showed s · s. . t a very earl . opposite was ever afte o~e superrority over the s ~f ~ge . the crossed grown tho t rwar s retained. When th e - crtihsed, which plants' in ~o tallest crossed and the t ~ plants were fully table. I r:~crt f~t were measured as ;:;,~w allest self-fertilised the pairs. b ttl at from want of time I d ~ m the following tho a vera~e ~ffi ~e tallest on each side sccme~ f.· I:olt measure all 01 once between the t 1 air y to repr·csent \YO .ots. No. of Pot. I. II. TABLE XXVIII. I Crosse~ Plants (two tallest m each pot). 12 11 ~ |