Natatory chaetae, of Nereidae, [277];

of Syllidae, [278], [307]

Nathusius, on parasites, [63], [163]

Nauphanta, [314], [315]

Nebalia, Rotifers parasitic on, [225]

Nectochaeta, [291]

Nectonema agile, [164], [168], [169], [173]

Nemathelminthes, [123] f., [168]

Nematobothrium, [4], [55], [71], [73]

Nematoda, [123];