170 Robertson : Theories of Evolution. 
of Erasmus Darwin. The opinions held by the two men were 
very similar, but Lamarck, who was primarily a scientist, worked 
out his theories much more completely and circumstantially, and 
they received more attention from naturalists than the compar- 
atively tentative ideas of a poet and dreamer such as Erasmus 
Darwin. Lamarck was born in 1744. His father destined him 
for the Church, but his own taste was for military things, and 
as soon as his father died he joined the French army, then 
campaigning against Germany. He distinguished himself so 
much in an action, which took place the day he enlisted, that he 
was made an officer on the spot. He was soon obliged to leave 
the army owing to ill-health, with a pension of only about 420a 
year. He was obliged to work at a bank to make this pittance 
up toaliving wage, andat the same time went throughsome medical 
studies. He worked at botany in his spare time, and produced 
his ‘Flore Frangaise,’ which brought him under the notice of 
Buffon, who made him tutor to his son. For fifteen years he 
lived precariously by his pen, but during the Reign of Terror he 
obtained the appointment of Professor at the Musée d’ Histoire 
Naturelle. His colleague, Geoffroy St. Hilaire (then twenty-one), 
was responsible for the Vertebrate Zoology, while Lamarck 
cheerfully undertook everything else! In 1809 his great work, 
the ‘ Philosophie Zoologique,’ saw the light. 
Lamarck had, in many ways, an unfortunate life. For many 
years he had a great struggle to make both ends meet, and for 
the last ten years of his life he was blind. His daughter Cornélie 
devoted herself to him absolutely, and became his scientific 
secretary. His poverty and his blindness do not complete the 
full tale of his sorrows, for, in the words of Professor Packard, 
his biographer, ‘ Lamarck’s life was saddened and embittered 
by the loss of four wives.’ 
To try and state Lamarck’s philosophy in a few words is 
extremely difficult. He believed that, in the main, two great 
factors had codperated in producing organic evolution. The 
first of these was a tendency inherent in all organisms to pro- 
gress from the simple and undifferentiated to the complex and 
highly differentiated. The second was the power of organisms 
to adapt themselves to their environment through habit and the 
use and disuse of organs, and to transmit to their offspring the 
adaptations so produced. For instance, Lamarck would suppose 
that the giraffe was descended from a short-necked ancestor, 
whose perpetual efforts to browse on higher and higher branches 
of trees produced a certain elongation of its neck. This 
Naturalist, 
