Instead of recognizing, as before, a subclass in the Ratitae of Merrem, Nitzsch now reduced them to the rank of an order under the name " Platysternae," placing them between the " Gallinaceae " and " Grallae," though admitting that in their pterylosis they differ from all other birds, in ways that he is at great pains to describe, in each of the four genera examined by him - Struthio, Rhea, Dromaeus and Casuarius.
5 It is significant that notwithstanding this he did not figure the pterylosis of any one of them, and the thought suggests itself that, though his editor assures us he had convinced himself that the group must be here shoved in (eingeschoben is the word used), the intrusion is rather due to the necessity which Nitzsch, in common with most men of his time (the Quinarians excepted), felt for deploying the whole series of birds into line, in which case the proceeding may be defensible on the score of convenience.
Yet it is said, on good authority, that Nitzsch had the patience so to manipulate the skins of many rare species that he was able to ascertain the characters of their pterylosis by the inspection of their inside only, without in any way damaging them for the ordinary purpose of a museum.
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