150 ORGANIC EVOLUTION — MENTAL 



" It was said by the late Dr. Robert Ball, that when 

 the common Sargartia parasitica is attached to a stone, 

 and a hermit crab is placed in its vicinity, the anemone 

 will leave the stone and attach itself to the hermit's 

 shell." — Animal Intelligence, p. 234. 



Instinct is certainly present in worms, as Darwin 

 proved. 



" Seeing that they always lay hold of the part of 

 the leaf (even though an exotic one) by the traction 

 of which the leaf will offer least resistance to being 

 drawn down." — Quoted by Professor Romanes in Animal 

 Intelligence, p. 24. 



" This animal is of a timid disposition, darting into 

 its burrow like a rabbit when alarmed." — Quoted by 

 Professor Romanes in Mental Evolution in Animals, 

 p. 344. 



Instinct is certainly present also in the molluscs, and, 

 as every one knows, it is developed to an astonishing 

 degree in the annulosa — e. g. insects ; and here also 

 may we detect the first glimmering of reason, if my 

 definition of it as " the faculty which is concerned in 

 the conscious adaption of means to ends by virtue of 

 acquired non-inherited knowledge and ways of thinking 

 and acting " be correct. 



" Even the headless oyster seems to profit from 

 experience, for Dicquemase {Journal de Physique, vol. 

 xxviii. p. 244) asserts that oysters taken from a depth 

 never uncovered by the sea, open their shells, lose the 

 water within, and perish ; but oysters taken from the 

 same place and depth, if kept in reservoirs, where they 

 are occasionally left uncovered for a short time, and 

 are otherwise incommoded, learn to keep their shells 



