Aeolosoma, [349], [353], [354], [360], [370], [374], [375]

Aetea, [518], [525]

Agassiz, on Syllidae, [280]

Alaurina claparedii, [49]

Albertia, [204], [210], [213], [224], [227]

Alciope, [315]

Alciopids (Alciopina), [314];

head, [263];

parapodium, [265];

habit, [291];