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observations and were thus descriptive in nature, whereas Camerarius was the first to con-
duct experiments. Malpighi’s contribution is often underappreciated because, far from
challenging the old plants- as- female model, he embellished it with contemporary clinical
terminology. Grew, whose treatise on plant anatomy was published shortly after Malpighi’s,
initially adopted Malpighi’s elaborate one- sex model but later added a novel feature of his
own: a transsexual stamen! But Grew did not base his new hypothesis on experimental
evidence. Rather, his theory was a philosophical compromise between a one- sex and a two-
sex model, which could be thought of as a “one- and- a- half- sex model.” It was left to the
experimentalist Camerarius to sever botany’s umbilical cord to classical botany once and
for all by providing the first experimental evidence for a straightforward two- sex model of
plant reproduction.Early Microscope Observations on Plants
Just as the telescope opened up the universe to human curiosity, the microscope revealed the
formerly invisible world of the very small. By 1600, technical improvements in glass- making
and lens- grinding in Holland had led to the invention of telescopes,^3 and, ten years later,
Galileo employed his own telescope to observe mountains on the moon and other celestial
objects. Galileo also adapted his telescope to magnify objects at close range, enabling him
to observe the compound eyes of insects. His reconfigured telescope, with its two lenses, is
referred to as a “compound microscope,” in contrast to a “simple microscope,” which con-
sists of a single lens mounted on a stand. Galileo and his colleagues, who called themselves
the Accademia dei Lincei (Academy of the Lynx- Eyed),^4 used the new compound micro-
scope to examine a wide variety of materials.
In the meantime, England and Holland were heating up as centers of microscopy
research. In 1628, the British physician William Harvey published his microscope obser-
vations of pulsating insect hearts, and, in 1663, Robert Hooke, who held the position of
Demonstrator at the newly established Royal Society of London, used a compound micro-
scope to view plant materials at close range, including moss “leaves” and thin sections
of cork. Hooke observed that both tissues were actually comprised of hundreds of tiny,
honeycomb- like chambers, which he called “cells.” His book of illustrations, Micrographia,
published in 1665, caused a considerable stir throughout Europe in the rapidly expanding
scientific community.
Hooke’s pioneering but somewhat haphazard microscope observations were soon taken
up more systematically by the young English physician Nehemiah Grew, then only twenty-
three years old, who chose to focus his efforts on plant structures. In the seventeenth cen-
tury. it was quite common to couch one’s scientific pursuits in religious terms, and Grew,
whose father was a Puritan clergyman, explained his decision to study plants as a means of
gaining insight into God’s wisdom. Meanwhile, in Italy, the physician Marcello Malpighi,
thirteen years Grew’s senior, had already established himself as an eminent authority
in the fields of anatomy, physiology, and embryology. Despite his fame, Malpighi was
under constant attack from conservative elements in the Italian medical community who
doubted the usefulness of applying modern scientific techniques to medicine.^5 In contrast,
Grew’s career was supported and encouraged by enthusiastic backers at the Royal Society
of London.