chondrostei

from The Collaborative International Dictionary of English v.0.48

Chondrostei \Chon*dros"te*i\, n. pl. [NL., fr. Gr. ? cartilage +
   ? bone.] (Zool.)
   An order of fishes, including the sturgeons; -- so named
   because the skeleton is cartilaginous.
   [1913 Webster]