Flora’s Secret Gardens j 495
495 495
Notes
- Darwin, Charles (1958), The Autobiography of Charles Darwin: 1809– 1882 , N. Barlow, ed.
Collins, p. 120. - von Sachs, J. (1906), History of Botany (1530– 1860), trans. H. E. F. Garnsey; revised by I. B.
Balfour. Clarendon Press, p. 200. Originally published in German in 1860.
3. Ibid.
4. Ibid. - It is worth noting that Darwin himself never pursued the question of the evolution of the
alternation of generations. Although the evolutionary relationship between the cryptogams and
the seed plants was taken for granted by plant morphologists after Darwin, there was a long
delay— several decades at least— before comparative morphologists began addressing the under-
lying selection mechanisms that gave rise to the plant life cycle. - Kaplan, D. R., and T. J. Cooke (1996), The genius of Wilhelm Hofmeister: the origin of
causal- analytical research in plant development. American Journal of Botany 83:1647– 1660. - The severity of nearsightedness is measured by the strength of the lens (in units of diopters)
needed to correct it. For example, a −6 diopter myope can achieve a magnification of 1.5× with
the naked eye by viewing an object at a distance of 6.2 inches. An even more severe −10 diopter
myope (probably similar to Hofmeister’s vision) can achieve a 2.5× magnification by viewing an
object at only 4 inches from the eye. See Gorelick, Leonard, and A. John Gwinnett (1981), Close
work without magnifying lenses: A hypothetical explanation for the ability of ancient craftsmen
to effect minute detail. Expedition Winter: pp. 27– 34. - Kaplan and Cooke, The genius of Wilhelm Hofmeister.
9. Ibid. - Hofmeister borrowed the term “Alternation of Generations” from zoology. The Danish
zoologist Japetus Steenstrup had used it to describe the alternating sexual and asexual stages of
the life cycles of certain invertebrates, such as tunicates, cnidarians, and trematodes. However,
as was discovered later, the alternation of generations in plants differs from that in animals
because the asexual sporophyte stage is diploid (having two sets of chromosomes), whereas the
sexual gametophyte stage is haploid (having one set of chromosomes). - Fern allies are not true ferns but are similar in that they are nonseed plants with vascu-
lar systems for the transport of water and nutrients. Like ferns, they release asexual spores and
exhibit the alternation of generations. - Selaginella is a heterosporous member of the Lycophyta, the oldest living Division of vas-
cular plants, which first appeared in the fossil record around 410 million years ago, during the
Silurian Period. There are about 700 species of Selaginella, most of which are small and delicate.
They are found in a variety of climates, including tropical, arctic, temperate, and desert. One
species, S. lepidophylla, is commonly known as the “resurrection plant.” It grows in the Mexican
desert and dries into a tight ball during droughts, but is able to resume growth upon wetting. - Gifford, E. M., and A. Foster (1987), Morphology and Evolution of Vascular Plants. W. H.
Freeman, p. 136. - Juniper “berries” have fleshy walls and superficially resemble fruits, but they are actually
ovulate cones comprised of a seed surrounded by small, scale- like leaves. Another apparent excep-
tion is the berry- like structures of members of the Ta x a c a e a, such as yew trees. The seeds of yew