252 LAMARCK, HIS LIFE AND WORK 
them germinate, the plant develops all its leaves in 
the air, and then none of them is divided into capil- 
lary points, which gives rise to Ranunculus hedcraceus, 
which botanists regard as a species. 
“‘Another very striking proof of the effect of a 
change of circumstances on a plant submitted to it is 
the following: 
“It is observed that when a tuft of Juncus biufonius 
grows very near the edge of the water in a ditch or 
marsh this rush then pushes out filiform stems which 
lie in the water, are there deformed, becoming dis- 
turbed (tracantes), proliferous, and very different from 
that of Juncus bufonius which grows out of water. 
This plant, modified by the circumstances I have just 
indicated, has been regarded as a distinct species; it is 
the Juncus supinus of Rotte.* 
“TY could also give citations to prove that the 
changes of circumstances relative to organisms neces- 
sarily change the influences which they undergo on 
the part of all that which environs them or which 
acts on them, and so necessarily bring about changes 
in their size, their shape, their different organs. 
“Then among living beings nature seems to me to 
offer in an absolute manner only individuals which 
succeed one another by generation. 
“‘ However, in order to facilitate the study and 
recognition of these organisms, I give the name of 
species to every collection of individuals which during 
a long period resemble each other so much in all their 
parts that these individuals only present small acci- 
dental differences which, in plants, reproduction by 
seeds causes to disappear. 
“But, besides that at the end of a long period the 
totality of individuals of such a species change as 
the circumstances which act on them, those of these 
individuals which from special causes are transported 
* Gramen junceum, etc. (Moris. hist. 3, sec. 8, t. 9, f. 4). 
yi 3 9,1. 4 
