Flora Unveiled

328 i Flora Unveiled

diverse substance and unfit for the generation of seeds. Hence perhaps I apply the not

unfitting derived name of menstrual purgations, which closely precede the moments

of conception in women, just as it [conception] succeeds the discharges of flowers. [In

this way] a defined portion of the sap is separated through the stamens and the leaves

of the flower. ... And since in the discharge of menstruation a certain maturity of

time is required ... so the production of flowers in plants similarly doesn’t succeed

immediately, but after a defined time.

According to Malpighi, “menstrual purgations” of flowers take various forms, including
the secretions of glandular hairs and, most significantly, pollen, which he called “globuli.”
Malpighi was the first to illustrate pollen grains and their release from anthers, which he
called globulorum capsulae (capsules of globules). Figure 12.2A shows pollen grains escap-
ing from the apertures at the tips of an anther of “Indian wheat” or maize. In his descrip-
tion of the figure, Malpighi again emphasizes the dynamic nature of the process:  “The
excited apertures at the summits allow the globules to exit.” The term “excited” (“awak-
ened,” “aroused”) applied to the anther, like the term “frantic discharge,” is sexually sug-
gestive. Figure  12.2B shows pollen exiting the anther of a squash plant (“Cucurbitae”).
According to Malpighi, “the capsule [anther] of globules acts as a junction which filters
the staminal material in the globules.” Presumably this statement refers to the role of the
anther in “menstrual purgation.” Thus Malpighi interprets the stamen as a female repro-
ductive structure.
Most historians of botany have concluded that Malpighi simply missed the boat on the
question of sex in plants. But neither Malpighi nor Laurenberg were true asexualists, any
more than Ruel was. The Laurenberg- Malpighi anthropomorphic menstruation model of
the flower feminized it to such an extent that it flung the door wide open to questions about
the missing male half of the equation. Chance favored the prepared mind, and Nehemiah
Grew seized the opportunity to provide the answer.

Nehemiah Grew’s Anatomy of Vegetables Begun

Nehemiah Grew’s ideas about flowers, unlike those of Malpighi’s, evolved over time.
Malpighi was already a mature researcher with a long list of discoveries in anatomy, physiol-
ogy, and embryology to his credit by the time he became interested in plants. His elaborate
analogies comparing flowers to the human female reproductive system were based on his
extensive first- hand knowledge of animal anatomy and physiology. In contrast, Grew was
barely out of Pembroke College, Cambridge, when he initiated his own botanical stud-
ies in 1664.^15 These early studies consisted of anatomical drawings of plants made without
the use of a microscope. His half- brother, Henry Sampson, brought Grew’s investigations
to the attention of Henry Oldenburg, the energetic Secretary of the Royal Society, who
promptly showed them to the Bishop of Chester, John Wilkins, a leading figure in the
Society. Wilkins presented them at a meeting of the Society, and the positive response led
to an offer to publish the work, The Anatomy of Vegetables Begun (1672), under the Society’s
imprimatur.
Grew’s discussion of floral anatomy in The Anatomy of Vegetables Begun could have been
written by any of the classical botanists. Like Jean Ruel before him, Grew metaphorically