Diachaeta, [366]

Diaphragm, of Nereis introvert, [250], [251];

of Terebellidae, [304], [327];

of Polyzoa, [469], [470], [500], [508]

Diaschiza, [225], [226]

Diastopora, [518], [531]

Dichogaster, [362], [383]

Diclidophora, [73]

Dicotylus, [32], [35], [36], [42]

Dicranotaenia, [91];