You'll find
here a very brief description of the type of beads you'll use for
making bead animals.
Seed
Beads:

These
sees beads
are the basic beads that we use for beading. They usually make up the
body of an animal. Nowadays, you can buy them in whatever color, size
and shape you want. I use quiet small (I don't know the exact size) and
round seed beads.
Pony
(Bigger)
Beads:
These
are much bigger than the seed beads. Once I heard that it's called as
'pony bead'. I usually use them for eyes of an
animal, but use them whenever you want to 'highlight' something.
Bungle (Long) Beads:
The
size of the bungle beads is between the seed beads and the pony
beads. I use them for wings, legs of an
animals body. (Eg.: half of the the dragonfly's body is made up of long
beads.)