by William Swainson

“ These birds, hitherto placed in systems under one genus, nevertheless contain two distinct groups differing materially in the construction of that primary organ of supporting life, the bill; and in their physical distribution, or the countries they respectively inhabit, two most important considerations in the natural arrangement of animals under the present elevated views of the philosophic zoologist, with whom the study of Nature consists no longer in the study of words, the retention of names, or even the accurate description of species. ”

“ Lewin observes, "it inhabits heads of rivers, visiting dead trees, from the branches of which it darts on its prey in the water beneath, and is sometimes completely immersed by the velocity of its descent." ”

“ Their bills seem formed for swallowing their food more in an entire state, similar to the Herons. In each of these genera one species exists with only three toes, a remarkable circumstance, which in an artificial system would endanger their being united in a separate genus; but which, from the remarkable smallness of the inner toe in all the other species, cannot I apprehend point out any peculiarity either in their habit or economy: and this opinion I find is likewise entertained by Professor Temminck. ”