LAMARCK’S THEORY OF DESCENT 207 
“A very dry spring-time is the cause of the grass 
of a field growing very slowly, remaining scraggy and 
puny, flowering and fruiting without growing much. 
“A spring interspersed with warm days and rainy 
days makes the same grass grow rapidly, and the har- 
vest of hay is then excellent. 
“ But if any cause perpetuates the unfavorable cir- 
cumstances surrounding these plants, they vary pro- 
portionally, at first in their appearance and general 
condition, and finally in several particulars of their 
characters. 
“For example, if some seed of any of the grasses 
referred to should be carried into an elevated place, on 
a dry and stony greensward much exposed to the 
winds, and should germinate there, the plant which 
should be able to live in this place would always be 
badly nourished, and the individuals reproduced there 
continuing to exist under these depressing circum- 
stances, there would result a race truly different from 
that living in the field, though originating from it. 
The individuals of this new race would be small, 
scraggy, and some of their organs, having developed 
more than others, would then offer special proportions. 
‘“Those who have observed much, and who have 
consulted the great collections, have become con- 
vinced that in proportion as the circumstances of 
habitat, exposure, climate, food, mode of life, etc., 
come to change, the characters of size, form, propor- 
tion between the parts, color, consistence, agility, and 
industry in the animals change proportionally. 
“What nature accomplishes after a long time, we 
bring about every day by suddenly changing, in the 
case of a living plant, the circumstances under which 
it and all the individuals of its species exist. 
“All botanists know that the plants which they 
transplant from their birthplace into gardens for cul- 
tivation gradually undergo changes which at last 
render them unrecognizable. Many plants naturally 
