魚の分類（14） Watson (1937)

Bergが13番目に示したのが，Watson (1937)の分類です．

ワトスン(D. Watson)は，Acanthodii（＝棘魚類）に関するモノグラフで，以下の分類を提案しています．

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branch AGNATHA
　order † HETEROSTRACI
　order † ANASPIDA
　order † OSTEOSTRACI
　order CYCLOSTOMATA
branch GNATHOSTOMATA

Grade and class † APHETOHYOIDEA. A complete gill slit between the mandibular and hyoid arches.
　order † ACANTHODII
　order † ARTHRODIRA
　order † ANTIARCHI
　order † PETALICHTHYIDA
　order † RHENANIDA

Grade PISCES. The gill slit between the mandibular and hyoid arches reduced to spiracle or closed completely.
　Class CHONDRICHTHYES
　Class OSTEICHTHYES

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*1: Watson, D. M. S., 1937, The Acanthodian fishes. Phil. Trans., series B, vol. 228, London. 1937, p. 125, 142.