from
The Collaborative International Dictionary of English v.0.48
Vertebrata \Ver`te*bra"ta\, n. pl. [NL.] (Zool.)
One of the grand divisions of the animal kingdom, comprising
all animals that have a backbone composed of bony or
cartilaginous vertebrae, together with Amphioxus in which the
backbone is represented by a simple undivided notochord. The
Vertebrata always have a dorsal, or neural, cavity above the
notochord or backbone, and a ventral, or visceral, cavity
below it. The subdivisions or classes of Vertebrata are
Mammalia, Aves, Reptilia, Amphibia, Pisces, Marsipobranchia,
and Leptocardia.
[1913 Webster]