ae 
and strains ; and (as Lamarck bids us observe), in spite of all 
the long-continued response to the earlier normal specific 
conditions, the innate congenital potentiality shows itself. 
The individual under the new quantities of environing agen- 
cies shows new responsive quantities in those parts of its 
structure concerned, new or acquired characters. 
“So far, so good. What Lamarck next asks us to accept, 
as his ‘second law,’ seems not only to lack the support of 
experimental proof, but to be inconsistent with what has just 
preceded it. The new character, which is ex hypothesi, as was 
the old character (length, breadth, weight of a part) which it 
has replaced—a response to environment, a particular mould- 
ing or manipulation by incident forces of the potential con- 
genital quality of the race—is, according to Lamarck, all of a 
sudden raised to extraordinary powers. The new or freshly- 
acquired character is declared by Lamarck and his adherents 
to be capable of transmission by generation ; that is to say, it 
alters the potential character of the species. It is no longer a 
merely responsive or reactive character, determined quantita- 
tively by quantitative conditions of the environment, but 
becomes fixed and incorporated in the potential of the race, so 
as to persist when other quantitative external conditions are 
substituted for those which originally determined it. In 
opposition to Lamarck, one must urge, in the first place, that 
this thing has never been shown experimentally to occur ; and 
in the second place, there is no ground for holding its oceur- 
rence to be probable, but, on the contrary, strong reason for 
holding it to be improbable. Since the old character (length, 
breadth, weight) had not become fixed and congenital after 
many thousands of successive generations of individuals had 
developed it in response to environment, but gave place to a 
new character when new conditions operated on an individual 
(Lamarck’s first law), why should we suppose that the new 
character is likely to become fixed after a much shorter time 
of responsive existence, or to escape the operation of the first 
law? Clearly there is no reason (so far Lamarck’s statement 
goes) for any such supposition, and the two so-called laws of 
Lamarck are at variance with one another.” 
These passages have been quoted at length because they 
