364 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1911. 
properties of the hydrogen and the oxygen which combine to form it, 
so the marvelous properties of protein are due to the assemblage of 
the properties of the carbon, hydrogen, and other. elements which 
enter into its composition. The molecules of pretein, in some at 
present unknown way, are built up so as to form the still more 
complex body, living protoplasm. 
The fundamental principle we have to bear in mind is that living 
protein, without alteration in its chemical composition, is capable of 
existing in a multitude of forms. As Prof. W. B. Hardy states, all 
proteids are not the same proteids; there are proteids of men, others 
of beasts, others of fishes, and others of birds. The properties of a 
complex substance like protein are defined not so much by the kind 
of atoms or number of elements of which it is built up, as by the 
structural arrangement and the motion of those atoms in space.? 
He gives as an example the molecules of two chemical substances, 
benzonitrile and phenylisocyanide, each of these being composed of 
seven atoms of carbon, five of hydrogen, and one of nitrogen. There 
is a small difference in the arrangement of these atoms; this differ- 
ence so alters the properties of the two substances that one is a harm- 
less fluid with an aromatic smell; the other an offensive poison. It 
is evident from the complex nature of the elements of a proteid that 
its molecules must be of far larger dimensions than the molecules of 
inorganic substances; but the larger the size the greater the proba- 
bility of variation of its elements in detail by the action upon them of 
various forms of energy. As we have elsewhere stated, it is, we hold, 
in consequence. of the unique structural arrangement and motion of 
the elements which constitute protoplasm, that it acts as a trans- 
former of chemical and other kinds of energy into phenomena char- 
acteristic of living matter.$ 
The majority of persons who have studied the subject are of opinion 
that organic evolution is a natural process, the existing orders of ani- 
mals and plants having been progressively developed out of specially 
adapted protoplasmic elements. Nevertheless, a considerable num- 
ber of educated people have misgivings on this subject, for they fail 
to comprehend how, if the various classes of animals have been gradu- 
ally evolved out of a common form of organic matter, it comes to 
pass that some of them should possess a nervous system, through 
means of which they have gained the power of guiding their actions 
1 The Doctrine of Evolution, by Prof. H. E. Crampton, p. 22. 
2 Science Progress, vol. 1, p. 195. 
3 It may be shown that we can fix certain qualities on the surface layer of solids such as protoplasm by 
the use of minute amounts of salts. The salts may be washed out, but its effects remain and exert a direct 
influence on the succeeding molecular events, so far this action lasts for all time in the absence of active 
chemical intervention. See Journal de Chem. Physique, vols. 2 and 3, pp. 61, 50; Human Speech, by N. 
C. Macnamara, International Scientific Series, vol. 95, p. 12. 
Prof. Villa, in his admirable work on Contemporary Psychology, states “‘What we call ‘life’ or biological 
organization is the result of a peculiar combination of elements,’’ pp. 268, 271. 
