212 BIOLOGY AND ITS MAKERS 
in its less grotesque form, his discoverv of the development 
of the eggs of plant-lice without previous fertilization, his 
researches on regeneration of parts in polyps and worms, 
and other observations place him among the conspicuous 
Fic. 64.—CHARLES BONNET, 1720-1793. 
naturalists of the period. His system of philosophy, which 
has been carefully analyzed by Whitman, is designated by 
that writer as a system of negations. 
In 1821, J. Fr. Meckel, recognizing the great value of 
