Invertebrate Rap

Ny name is Sean,
And I'm here to say,
That I'm gonna talk
About invertebrates today!
First there's Porifera,
Including sponges too,
They've got no brains --
Hey, watcha gonna do?
Then there's Cnidaria,
Like jellyfish an'stuff
They're stinging-cell animals,
If they sting you, that's tough!
Now for Platyhelminthes
Planaria, flukes tapeworms,
Some parasites, some free-living,
Just worms in layman's terms!
How bout Nematoda?
Well, the name says it all!
They got nematodes,
Well, Duh! Y'all!
Now on to Mollusca,
Bivalves, snails, slugs,
There's also octopusses,
I don't think they're fun t'hug!
Annelida, Annelida,
That's next on the list,
They got segmented worms,
and you know they're the coolest!
Echinodermata,
They all begin with "sea"!
Star, cucumber, dollar, urchin,
They're not like me!
Arthropods next,
Arachnids ahoy!
Crustaceans too,
Oh, what joy!
Last is Chordata,
They got nerve chords, yo!
Wait, some are vertebrates
Oops! Uh-oh.
So my name is Sean,
And I wanna say,
That I had fun
With invertebrates
Today!