On the other hand it is highly probable that with many animals the embryonic or larval stages show us, more or less completely, the condition of the progenitor of the whole group in its adult state. In the great class of the Crustacea, forms wonderfully distinct from each other, namely, suctorial parasites, cirripedes, entomostraca, and even the malacostraca, appear at first as larvae under the nauplius-form;
Oso gertagarria da, ordea, enbrioi edo larba-egoerek, animalia askotan, talde osoaren gurasolehenak bere heldu fasean izaniko egoera gehiago edo gutxiago osorik erakustea. Krustazeoen klase zabalean bata bestetik arras bereiziak diren formak, hots, bizkarroi zurgatzaileak, zirripedioak, entomostrazeoak eta malakostrakoak berak ere, nauplius-eran agertzen dira hasieran;