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Show 128 HETEROSTYLED Dil\iORPHIC PLANTS. CHAP. III. ·short-styled flowers a similar brush of hairs is situated low down within the tubular corolla, above the stigma and beneath the anthers. The presence of these beaded hairs in both forms, though occupying such different positions, shows that they are probably of considerable functional importance. They would serve to guard the stigma of each form from its own pollen; but in accordance with Prof. Kerner's view* their chief use probably is to prevent the copious nectar being stolen by small crawling. insects, which could not render any service to the species by carrying pollen from one form to the other. The flowers are so small and so crowded together that I was not willing to expend time in fertilising them separately ; but I dragged repeatedly heads of short-styled flowers over three long-styled flower-heads, which were thus legitimately fertilised; and they produced many dozen fruits, each containing two good seeds. I fertilised in the same manner three heads on the same long-styled plant with pollen from another long-styled plant, so that these were fertilised illegitimately, and they did not yield a single seed. Nor did this plant, which was of course protected by a net, bear spontaneously any seeds. Nevertheless another long-styled plant, which was carefully protected, produced spontaneously a very few seeds; so that the long-styled form is not always quite sterile with its own pollen. FARAMEA [sP. ?J (RUBIA~ElE). Fritz Muller has fully described the two forms of this remarkable plant, an inhabitant of South Brazil. t In * 'Die Schutzmittel der Billthen gegen unberufene Gaste,' 1876, p. 37. t 'Bot. Zeitung,' Sept. 10, 1869, p. 606. CHAP. III. FARAMEA. 129 the long-styled form the pistil projects above the corolla, and is almost exactly twice as long as that of the short-styled, which is included within the tube. The former is divided into two rather short and broad stigmas, whilst the short-styled pistil is divided into two long, thin, sometimes much curled stigmas. The stamens of each form correspond in height or length with the pistils of the other form. The anthers of the short-sty led form are a little larger than those of the long-sty led ; and their pollen -grains are to those of the other form as 100 to 67 in diameter. But the pollen-grains of the two forms differ in a much more remarkable manner, of which no other Fig. 9. . Short-styled form. Long-styled form. Outhnes of flowers from ~ried spec~~ens. Pollen-grains, magnified 180 times, by Fntz Muller. F ARAMEA [ sp. ?]. in~tance is known ; those from the short-sty led flowers being covered with sharp points; the smaller ones K |