4 Comparative Physiology and Psychology. [January, 
originates it. Without dipping into biogenesis, spontaneous gen- 
eration somewhere, somehow, is consistent with the groundwork 
of our essay, but we will avoid its consideration. 
Spallanzani, Dugés, Doyére and others have demonstrated that 
Infusoria and certain low worms, the Rotatoria, Tardigrada and 
some Crustacea are capable of desiccation and revival. The sus- 
pension of the major evidence of life function by animals under 
changed conditions, whether this be absolute desiccation or not, 
the development of seeds and ova, after indefinite quiescence, 
point toward if they do not fully attest the merging of the inor- 
ganic into the organic, and the addition of the faculty known as 
life through the restoration of the medium which affords the 
means for the molecular motions which go to make up all there 
is in life. So the restoration of frozen fish, and as Semper cites: 
“ Amphibia, Mollusca and other forms have lived years without 
food.” He “kept species of land snails for years, wrapped in 
paper and quite dry, in wooden boxes, and thus wholly without 
food, and many of them are at this day alive and active.” His 
explanation is: “ The amount of nourishment required daily by 
any animal must naturally be equivalent to the organic matter 
which is daily used up in the various organs to keep up the vital 
processes ; the more active an animal is the more food will it 
require. But the vital processes of animals as low in the scale as 
Amphibia or univalves are extremely feeble; their respiration, 
even under the agitating influence of propagation, fails to raise 
temperature appreciably. In such the vital processes RA be 
reduced to a minimum without loss of life.” 
The whole matter is one of degree, for warm-blooded animals 
live but a little while unfed. Hibernates are comparable in con- 
dition to “ cold-blooded,” while this division sustain an arrest ot 
nutrition longer, and finally in the lowest forms the approach to- 
ward almost indefinite suspension leads us to think that there is 
a point where life and mere chemical conditions are identical. 
The repeated withdrawal of that which renders life evident entails 
no permanent inconvenience. Such embryos as are capable of 
living in a medium such as strong alcohol several days, point to 
the mechanical nature of certain low stages of life and the dimin- 
ished liability to destruction of initial forms through heteroge- 
neity of environment. The internal tissues of man, with their 
great range of chemical natures of fluids in which the cells 
Seems ber Reet ere ae ie aaa 
