Marcu 21, 1912] 
LETTERS: TO THE EDITOR. 
{The Editor does not hold himself responsible for 
opinions expressed by his correspondents. Neither 
can he undertake to return, or to correspond with 
the writers of, rejected manuscripts intended for 
this or any other part of Nature. No notice is 
taken of anonymous communications.] - 
Acquired Characters and Stimuli. 
Dr. ArcupaLt Rerp is usually so luminous in his 
statements concerning heredity that I hesitate to 
express my disagreement with what he has written in 
Nature of February 29, and elsewhere previously, as 
to the use of the term ‘‘ acquired characters.’’ It is, 
of course, true with regard to this term, as with re- 
gard to a great many others, that it can be inter- 
preted to mean what its original user, namely, 
Lamarck, did not mean, But I cannot see that any- 
thing is gained by so, doing. On the contrary, in 
such cases it seems to me best to endeavour to keep 
the term for what its introducer meant by it. I 
also fail to see any advantage in grouping together 
the various necessary chemical and physical environ- 
ments of a living thing under the word ‘‘ stimuli.’’ 
They do not become changed in nature by the appli- 
cation to them of that term, which is customarily used 
with more limited application. 
It is, of course, true (and I should suppose 
thoroughly familiar to every biologist) that the repro- 
ductive germ of an organism unfolds or ‘‘ develops” 
in response to the action upon it of certain surround- 
ing conditions—its environment. When those condi- 
tions are ‘“‘normal,”’ a normal germ develops in 
response to them—the normal characters of the 
species. When the conditions to which the- young 
organism is exposed are in some limited degree and 
in regard to certain ascertainable factors abnormal, 
the organism develops (in some cases) one or more 
abnormal characters differing from those developed 
by an otherwise equivalent specimen retained in the 
normal environment. The new _ character or 
characters developed in response to the abnormal 
environment (which we assume to be allowed to act 
on the growing young organism only, and not on 
its parents) are called by Lamarck—and by thosé who 
wish to discuss Lamarck’s theory—* acquired 
characters”’ (changements acquis). The word 
“‘acquire’’ is used to mean ‘‘something added to” 
or ‘‘changed in” the normal form of the species. 
It is not, I think, permissible to say that the 
normal characters which arise in response to normal 
conditions are with equal fitness to be described as 
“acquired.’’ Of course, all the characters successively 
developed by a growing reproductive germ or young 
organism may be spoken of as ‘‘acquired”’ by the 
organism during its growth from extreme youth to 
age. But to do so when discussing Lamarck’s 
theory is deliberately to create confusion. The thing 
in addition to and upon which ‘“‘acquirements”’ are 
made is, in Lamarck’s use of the word “acquire,” 
not the growing individual, but the normal specific 
form as exhibited in normal individuals. That, I 
take it, is Lamarck’s meaning, and it is that which 
I and others have for more than twenty-five years 
accepted. I am sorry to say that to use the word 
“acquired” at this period of a historical discussion, 
in another sense, is what an unfriendly critic (which I 
am not) would call ‘“quibbling,”” and, moreover, 
quibbling without any discernible object or purpose. 
I should like once more to point out (as I did many 
years ago in a similar correspondence in these pages) 
that the measurable factors of the normal environ- 
ment of a species of plant or animal often exhibit 
NATURE 
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61 
and intensity. This range differs in different species 
and groups of organisms, but, as a rule, the normal 
specific form is developed under conditions which are 
not very closely limited. A species is usually so 
“wound up” (to use a metaphor) as to be stable 
under a wide range of conditions. Outside that 
range we find first a zone or area of excess or de- 
crease of one or more factors of environment, such 
as heat, light, moisture, mechanical pressure, 
chemical character of food, &c., within which the 
organism still flourishes whilst giving new or 
abnormal responses to the new and abnormal quanti- 
ties of the environmental factors. These responses 
are Lamarck’s changements acquis—our “acquired 
characters ’’—characters which are not those of the 
species when existing in the by no means narrowly 
limited range of factors which are its normal environ- 
ment. 
Beyond this zone or area of potential (or tolerable) 
environment with its corresponding potential develop- 
ment of acquired characters not normal to the species 
in normal environment, we come to a further zone 
of larger increase or decrease of environmental 
factors. Here the organism does not respond as a 
living thing; it has no reserved potentialities which 
are called into activity by this further increase or 
decrease of one or more of the factors of the environ- 
ment; the environment ‘has become impossible or 
destructive, and the organism ceases to live. 
It is important to distinguish these three zones of 
limitation in increase or decrease of factors of the 
environment for every species, the normal, the poten- 
tial, and the destructive. It is a necessary part of 
bionomic inquiry to determine the range plus and 
minus of the several factors of each quality of 
environment—normal, potential, and destructive—in 
regard to whole series of species of both plants and 
animals. E. Ray LanKEsTER. 
Bournemouth, March o. 
Coordinated Purchase of Periodicals in two 
Newcastle Libraries. 
In 1905 Dr. Thomas Muir read a paper before the 
Royal Society of Edinburgh entitled ‘* Library Aids 
to Mathematical Research,” in which he urged that 
unnecessary duplication in the purchase of periodicals 
should be avoided by adjacent libraries. The matter 
has been taken up in Nature, e.g. in vol. Ixxxvii., 
p- 222. The following brief account of what is being 
done in this regard in Newcastle-upon-Tyne may 
therefore be of interest. 
In 1908 representatives of several Newcastle institu- 
tions met in the Public Library, at the invitation of 
the public librarian (Mr. Basil Anderton), to consider 
whether any coordination could be effected as regards 
the purchase of certain learned societies’ journals and 
some of the more expensive and less used periodicals. 
Armstrong College was represented by Profs. Bed- 
son and Jessop. Prof. Duff, who had for a consider- 
able time manifested cordial sympathy with the pro- 
ject, was unavoidably absent from the meeting. In 
the course of discussion various journals were named 
in regard to which concerted action seemed desirable, 
but for one reason or another, while the principle was 
commended, only the representatives of the Public 
Library and Armstrong College were at the time 
ready to take practical steps in the matter. 
Prof. Jessop moved that a beginning be made with 
certain mathematical journals, and that of those that 
were being bought in duplicate (one by each institu- 
tion) some be discontinued, and that the money so 
set free be applied to the covering of fresh ground. 
The suggestion, as modified by discussion and finally 
within that normal limit a great range in quantitv | moved by Prof. Jessop, was approved, and the public 
NO. 2212, VOL. 89] 
