THE LOLVPES, 81 
experience, of education, which to them supplies the place of every 
intelligence. Instinct and intelligence are two faculties which 
compensate each other, the one supplies the place of the other. 
Instinct is the intelligence of the lower animals. 
The marine polypes resemble those of the fresh water. The 
animals of these species are always composed of a sack-like body, 
which possesses an opening surrounded by many arms. The body 
may be long or short; sometimes it is narrow like a quill pen, 
sometimes round like a purse, and occasionally funnel-shaped. 
The opening varies in size, but always serves the double purpose 
of admitting the food and ejecting the excrement. A diversified 
construction of the sac renders the creature somewhat more or 
less complicated. In some of the higher forms it is often a dis- 
tinct tube surrounded by vertical canals, into which open curious 
organs in the form of intestines. The arms are variable as to 
their number ; sometimes twelve are found, but generally not more 
than eight ; they resemble the cilia of the infusoria, or bear a com- 
parison to tendrils or petals; their edges are often barbed. Taking 
this organisation of the green hydra as a type, and varying it in 
every conceivable manner, nature has peopled the ocean with those 
animals which are termed zperfect. 
