Tunicata

Ahhh, but do you know where the name comes from?

Tunicates have a stiff "coat" or "shell" that protects their body. A "tunic", if you will.

And to spoil the wonderful beginning of SEFs writeup, it's not actually going back through the family tree, since all organisms that are still alive now have evolved as much as we have. It's more like having a distant cousin that is a professional wrestler, a wino, or a congressman.

Tu`ni*ca"ta (?), n. pl. [NL. See Tunicate.] Zool.

A grand division of the animal kingdom, intermediate, in some respects, between the invertebrates and vertebrates, and by some writers united with the latter. They were formerly classed with acephalous mollusks. The body is usually covered with a firm external tunic, consisting in part of cellulose, and having two openings, one for the entrance and one for the exit of water. The pharynx is usually dilated in the form of a sac, pierced by several series of ciliated slits, and serves as a gill.

⇒ Most of the species when mature are firmly attached to foreign substances, but have free-swimming larvae which are furnished with an elongated tail and somewhat resemble a tadpole. In this state the larva has a urochord and certain other structures resembling some embryonic vertebrates. See Ascidian, Doliolum, Salpa, Urochord, and Illust. of Social ascidian, under Social.

© Webster 1913.