_ 1891] Are Acquired Variations Inherited ? 195 
is only as to the extent of its action. Second, we need not discuss 
the inheritance of mutilations, for mutilations are not part of the 
regular order of nature, and while they might have strong positive, 
they have little negative, value; the elaborate arguments which 
have been recently directed against them, remind us, therefore, of 
Don Quixote’s excursions against the windmills, as if Lamarckism 
mainly depended upon such evidence. Nor is it in dispute 
whether the effects of general atrophy or hypertrophy of the body 
are transmitted, for it is self-evident that an ill-fed organism will 
not bear as perfect offspring as a well-fed organism. As to 
pathological atrophy or hypertrophy, it is, I believe, admitted on 
both sides that in cases where it arises from certain bacilli it is 
possible that it may be transmitted with the bacilli. What we are 
discussing is whether the special and local variations in function 
and structure induced by environment and habit in the life of the 
parent tend in any degree to reappear in the offspring. © 
This is the modern or modified form of Lamarck’s law. His 
followers admit that he overestimated the rate of inheritance of the 
effects of use and disuse in stating that ač that is acquired is trans- 
mitted.” The element of rate or time is a secondary one, as it is 
with the law of Selection; the main point is whether such effects 
are transmitted at all. Of course there are Lamarckians of all 
degrees of fervor. The following statement probably reflects the 
average opinion : 
I. In the life of the individual, adaptation is increased by local 
and general metatrophic changes, of necessity correlated, which 
take place most rapidly in the regions of least perfect adaptation, 
since here the reactions are greatest. 2. The main trend of varia- 
tion is determined not by the transmission of the full adaptive 
Modifications themselves, as Lamarck supposed, but of the dispo- 
sition to adaptive atrophy or hypertrophy at certain points." 
“10 Quatritme loi: Tout ce qui a été a. tracé ou changé, dans l’organization 
wni individus, , pendent le cours de leur vie, est c la génération et — 
cage éprouvé ces changemen’ 
= Osborn, -Tbe Paleontological Evidence for the Transmission of Acquired Char- 
Adv. 
acters.” Brit. Assoc. Reports ; : Science; 1889. 
Dr. W. H. Dall has nE Bist A castally considered statement in his paper 
on“ Drask Influences in Evolution,” May 8th, 1 
