No. 387.} THE PRESENT STATUS OF ANATOMY. 195 
authority of Cuvier and the theological bias of his theory gained 
the day, however; the doctrine of transformationism retired 
temporarily from the field, and anatomy retained its isolated 
position. 
Attention has already been called to the inauguration of . 
the science of embryology by Fabricius and his pupil Harvey. 
During succeeding years it languished somewhat, but was finally 
established as an important branch of biology in the present 
century by the publication of the Beobachtungen und Reflexio- 
men of von Baer in 1829. A masterly study of the develop- 
ment of a number of vertebrate organisms led von Baer to 
formulate a principle of developmental unity by his doctrine of 
the germ layers, and also to establish an idea of transforma- 
tionism for the individual by demonstrating that in its develop- 
ment the organism proceeds from a more generalized to a more 
specialized condition ; that is to say, it presents first what for 
convenience may be termed type characteristics, later the family, 
then the generic, and then the specific peculiarities being added 
or superimposed. 
About the same time important ideas were working out in 
another department — that established by Malpighi and Leeu- 
wenhoek— microscopical anatomy. . Improvement of the micro- 
scope made possible the discovery in 1838 by the botanist 
Schleiden of cells as the ultimate structural units of plants — 
a discovery completed in the following year by Schwann, 
who extended the generalization to animals, and at the same 
time materially modified the meaning attached to the word cel. 
These discoveries were the following out of the idea of analysis 
suggested by Bichat, and were indeed the analysis of his tissue 
elements into individuals of a still lower grade. A further step 
was, however, still necessary to convert the cell-theory of struc- 
ture into its modern form, and that was the formulation of the 
protoplasmic theory by Max Schulze in 1861. Just as cells had 
been known long before the cell theory was postulated, so, too, 
protoplasm had been known ever since the amceba was first 
observed by Résel von Rosenhof in 1755. The attention to 
the nature of the cell contents, awakened by the cell theory, led 
the botanist von Mohl to recognize in vegetable cells a viscous 
