chaetognatha
Chæ*tog"na*tha, n. pl. Etym: [NL., from Gr. (Zoöl) Defn: An order of free-swimming marine worms, of which the genus Sagitta is the type. They have groups of curved spines on each side of the head.
Chæ*tog"na*tha, n. pl. Etym: [NL., from Gr. (Zoöl) Defn: An order of free-swimming marine worms, of which the genus Sagitta is the type. They have groups of curved spines on each side of the head.