Myzostomaria, [241];

structure and affinities, [342] f.

Myzostomatidae, [342]

Naidomorpha (= Naididae and Naids), [348], [352], [375] f., [377], [378], [400];

chaetae, [350], [367];

reproductive organs, [361];

asexual reproduction, [281], [377]

Nais, [348], [377];

chaetae, [350]

Nannodrilus, [382] f.