Word Study
heteronereis
CIDE DICTIONARY
A free-swimming, dimorphic, sexual form of certain species of Nereis. [1913 Webster]
" In this state the head and its appendages are changed in form, the eyes become very large; more or less of the parapodia are highly modified by the development of finlike lobes, and branchial lamellæ, and their setæ become longer and bladelike." [1913 Webster]
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