Biology 4 kids
Biology4 Kids: Annelids Worms With Segments
If you've dodged earthworms along the sidewalk after a rainfall then you have observed annelids. This text highlights these and other segmented worms.
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University of Aberdeen: The Phyla of Kingdom Animalia
Very systematic breakdown of the animal kingdom starting with the simplest type the sponge, all the way to the chordate or vertebrate. Each phylum has a link with information.