162 LAMARCK, HIS LIFE AND WORK 
This is certainly a sufficiently vague and unsatisfac- 
tory theory of spontaneous generation. This sort of 
cuess-work and hypothetical reasoning is not entirely 
confined to Lamarck’s time. Have we not, even a 
century later, examples among some of our biologists, 
and very eminent ones, of whole volumes of @ priorz 
theorizing and reasoning, with scarcely a single new 
fact to serve as a foundation? And yet this is an 
age of laboratories, of experimentations and of trained 
observers. The best of us indulge in far-fetched 
hypotheses, such as pangenesis, panmixia, the exist- 
ence of determinants, and if this be so should we not 
excuse Lamarck, who gave so many years to close 
observation in systematic botany and zodlogy, for 
his flights into the empyrean of subtle fluids, con- 
tainable and uncontainable, and for his invocation of 
an aura vitalis, at a time when the world of demon- 
strated facts in modern biology was undiscovered and 
its existence unsuspected ? 
The Preéxistence of Germs and the Encasement 
Theory.—Lamarck did not believe in Bonnet’s idea 
of the “‘preexistence, of, germs. ~ He asks whether 
there is any foundation for the notion that germs 
“successively develop in generations, z.e. in the mul- 
tiplication of individuals for the preservation of 
species,” and says: 
“J am not inclined to believe it if this preéxistence 
is taken in a general sense; but in limiting it to in- 
dividuals in which the unfertilized embryos or germs 
are formed before generation, I then believe that it 
has some foundation. —They say with good reason,’ 
he adds, ‘that every living being originates from 
