198 SECTIONAL ADDRESSES. 
history, but to the few it may recall some happy days and some moments 
of inspiration. 
Then the angiosperms: but here I stop, for the commemoration of 
those who laid the foundations of this knowledge might be wearisome, for 
their names, which include many already mentioned, unlike the names 
of the plants they studied, hardly sing themselves as they run. A welter 
of facts were discovered many of which, especially those relating to the 
Thallophyta, had to await the arrival of a new technique, that of cytology, 
before co-ordination was possible; but for the Muscines, the vascular 
cryptogams and the angiosperms the times produced the man whose 
patient and detailed work, directed by a keen intellect, gave cosmos to 
morphological enquiry. I refer to Hofmeister, one of the greatest botanists 
of all time. He first traced the development of the sexual organs and of 
the embryo in the angiosperm, and then turned to the vascular cryptogams 
and the Muscinee and did likewise. He was the first correctly to interpret 
heterospory: he correlated the asexual spore with the gametophyte and 
the oospore with the sporophyte ; he discovered alternation of generations. 
Nowadays alternation of generations is accepted as a matter of course, 
but when it is realised that Hofmeister was working it out, almost cell 
for cell, more than eighty years ago without the aid of the microtome and 
of cytological technique, as we know it, it will be appreciated how great 
was his work. Sachs’ judgment, here at any rate, was just: ‘ Embryology 
was the thread which guided the observer through the labyrinth of com- 
parative and genetic morphology ; metamorphosis now received its true 
meaning, when every organ could be referred back to its parent form, the 
staminal and carpellary leaves of the phanerogams, for example, to the 
spore bearing leaves of the vascular cryptogams. That which Hiackel, 
after the appearance of Darwin’s book, called the phylogenetic method, 
Hofmeister had long before actually carried out, and with magnificent 
success. When Darwin’s theory was given to the world eight years after 
Hofmeister’s investigations, the relations of affinity between the great 
divisions of the vegetable kingdom were so well established and so patent, 
that the theory of descent had only to accept what genetic morphology 
had actually brought to view.’ 
Anatomy.—In considering the development of anatomical knowledge 
during this epoch in some small measure of particularity, it is realised that 
although the many contributed in varying degrees to knowledge, the 
great advances were associated with the names of relatively few men. 
Of these, Schleiden and Schwann, the zoologist, are the first to be com- 
memorated since they laid the foundation of the scientific study of 
anatomy in their theory of the cell which, in a few words, was that the 
cell is the unit of structure and function in the organism. This, to-day, is 
a platitude, but in 1838 it was a thesis of the greatest importance since it 
enabled the co-ordination of, hitherto, jumbled facts into orderly con- 
ceptions, and enabled others, especially von Mohl and Nageli, to build 
knowledge of the anatomy of plants on a sound basis. Von Mohl dis- 
criminated the tissue elements and traced the course of the vascular 
system, and thus paved the way to comparative work. He was the first 
accurately to trace the development of vessels even to the partial oblitera- 
Sion of the originally partitioning walls of the superposed elements, and 
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