Sentence:  We here, at length, arrive at a sufficiently marked interruption of the series of the class of Birds, to be enabled to introduce some remarks on the affinities of the preceding orders, which we conceive might be arranged most naturally as follow. / I. Scansohes, as limited to the Parrots. / II. Raptores, or the Birds of Prev; which subdivide into two thoroughly distinct sections. / III. Strepitores, <WSD>Screechers</WSD>, consisting of all the remainder that are not organized upon the definite type of the Passerine;. It is necessary to subdivide them first into three series, which might be designated Syndactyli, Zygodactyli, and Heterodactyli; the two first of which names, however, do not rigidly apply in every instance, the groups being founded rather upon the aggregate of the organization, than upon any single character. 
Meaning of the word marked with <WSD> tags:  A bird of the former category (order), distinguished from the songbirds. (en)