THE SHELL-FISH OF THE COAST. 9 
it may be, is next to the backboned or vertebrate 
animals—the fishes, reptiles, birds, and quadru- 
peds—about the most complex, or, if you choose, 
most highly organized, of the entire animal series. 
It takes precedence over the star-fish, insect, crab, 
and lobster, and, among its own class, over the 
snail, clam, and oyster. It alone among the thou- 
sands—nay, hundreds of thousands—of invertebrate 
animals, or those lacking a backbone, possesses a 
distinct covering or capsule to its principal nerve- 
mass, the brain, thus foreshadowing the structure 
which is so distinctive a feature of all the higher 
animals. The skull 
of the cuttle-fish has 
not yet, ‘however, 
been converted into 
bone, but remains ina 
cartilaginous condi- 
tion, recalling in great 
measure the condi- 
tion of the skull in 
some of the lower 
fishes, the sharks 
and rays and _ stur- 
geon, for example. 
Again, we note a 
special development 
of the sense organs. The great round eyes that 
are situated on either side of the head have a per- 
fection but little inferior to that of the eyes of the 
highest animals, and are provided, although in a 
somewhat different order of: arrangement, with the 
EGG-CASES OF LOLIGO (‘SEA-GRAPE’). 
