Humboldt’s Araijari belongs to section E, where it will range between Pter. viridis and
Pter. inscriptus’, as,
Pter. Humboldtii; with the bill yellow, black on its culmen at its tip and base, blotched
with black at its serratures, and with the under mandible black.
Langsdorffs, Natterer’s, and Reinwardt’s Ara9aris belong to section F, with the following
distinctive characters:
Pter. Nattereri; with the bill red, marked at the base of each mandible with a large black
spot, and having the culmen and five or six blotches along the edge of the upper
mandible also black.
Pter. Reinwardtii; with the bill reddish at the base, with several black spots near the
cutting edge of the upper mandible, and w ith the culmen and terminal half blackish
brown.
Pter. Langsdorjjii; with the bill throughout nearly black, becoming slightly grey towards
its base.
Pter. pavoninus, Derbiamis, and hcematopygus will range in the seventh or last section, Gy
and are thus characterized :
Pter. pavoninus; with the under tail-coverts and tips of the tail-feathers brown, and the
lower mandible and base and cutting edge of the upper black.
Pter. Derbianus; with the under surface green throughout, and the tips of the two intermediate
tail-feathers chestnut.
Pter. hcematopygus; with the under surface green throughout, and the upper tail-coverts
blood red.
As all the species comprised in this latter section appear to possess characters sufficiently
distinct to warrant their separation as a peculiar genus, I propose to regard them in that light,
and to give them the generic title of Aulacorhynchus, with the following characters :
B ill comparatively short, furrowed on the sides; culmen broad and flattened ; base of the
under mandible extending obliquely beyond the line of the eye. Wings short and round, the
fourth quill-feather the longest, the fifth, sixth, and seventh being nearly of the same length.
Tail comparatively short and less decidedly graduated than in Pteroglossus.—The whole of this
group are characterized by a uniform green plumage, the feathers of which are loose and decomposed
in their texture.
Genus Ramphastos, Linné.
C h a r a c t e r e s G e n e r i c i .
Rostrum capite longius, maximum, crassum, inane, cultratum, margine basali incrassato; maxillæ angulo
frontali subtruncato transverso : nares verticales, pone maxillæ basin sites : tomia serrata : lingua
angusta, pennacea. Cauda brevis, oequalis.
B ill very large, longer than the head, thick, light, curved, and thickened at the basal margin ; the frontal
angle transversely subtruncated ; margins serrated. Nostrils vertical, behind the base o f the bill. Tongue
slender, long, and feathered. Tail short, even.