If we went up in a balloon and saw an aeronaut throw 
out ballast when he wanted to ascend and let out gas 
when he wanted to descend, we should never doubt that 
he was an intelligent being and that he knew perfectly 
well what he was about. Moreover it would be difficult 
to conceive of any action which more required the con 
stant supervision of the intelligence. We constantly meet 
with similar statements made by other writers. Thus 
Professor Henry Calderwood says :— 
“No one will propose to assign intelligence to the jelly-fish, star 
fish, snail, and centipede, though no one denies to them sensibility 
and motor activity.”—(The Relations of Mind and Brain, p. iq8.) 
So far as the first-mentioned animal is concerned, Mr. 
Romanes says:— 
“ This jelly-fish carries its larvae on the inner sides of its bell-like 
body. The mouth and stomach of the jelly-fish hang down like the 
tongue of a bell, and contain the nutrient fluids. Now, McCready 
observed this depending organ to be moved first to one side and 
then to the other side of the bell, in order to give suck to the larvae on 
the sides of the bell—the larvae dipping their long noses into the 
nutrient fluids which that organ of the parent’s body contained. I 
cite this case because, if it occurred in one of the higher animals, 
it would properly be called a case of instinct; but as it occurs in so 
low an animal as a jelly-fish, it is quite impossible that intelligence 
can ever have played any part in originating the action. Therefore 
we may set it down as the uncompounded result of Natural Selection.” 
—(Science Lectures.) 
And yet the same author says:— 
“ I observed jelly-fish crowding into the path of a sunbeam shining 
through a darkened tank, and saw that they did so in order to follow 
the crustaceans on which they feed, and which always seek the light.” 
—(.Mental Evolution in Animals, p. 258.) 
This has certainly the appearance of an intelligent action. 
With respect to the star-fish, “it is believed that the 
mother star-fish exercises a degree of watchfulness alto 
gether unusual among marine animals of so low a grade.”