ILLUSTRATIONS OF ORNITHOLOGY. 
TACHYPHONUS RUFIVENTER, Spix. 
Tanagra rufiventer, Spi, Av. Braz. v. 2, pl. 50, f. 1. 
THis species is remarkable for possessing six or seven distinct 
though rather irregular denticulations, directed forwards as in the 
Toucans, on the medial portion of the margins of both mandibles. 
This peculiarity of structure might almost justify the formation of 
a new genus, were it not that the close resemblance of its colo- 
ration to that of Tachyphonus desmaresti, and of T. cristatus, 
proves an intimate affinity to exist between these three birds. In 
Tachyphonus cristatus there is a single prominent undulation, 
almost amounting to a tooth, on the margin of the upper man- 
dible, which leads us to the closely allied genus Lanio, where this 
tooth is still more deyeloped. Inthe genus Pyranga@ also, we 
find marginal serrations, more or less conspicuous in the different 
species, so that this structure is by no means anomalous in T'ane- 
grine forms. 
The genus Phytotoma, well known for its serrated mandibles, 
belongs, there can be no doubt, to the family of Tanagers ; but it 
is distinguished from all the other genera, by possessing a double 
margin to the lower mandible, of which the inner one is serrated, 
the outer plain. 
The figure of this bird was drawn before I noticed that the species 
had been already figured by Spix. He, however, omits all notice of 
the denticulations of the beak. 
Front and sides of head, hind neck, upper back, wings, upper 
tail-covers, and tail, black; proximal portion of lesser wing-covers 
white ; crown yellow; lower back and rump ochre yellow ; throat 
ochre yellow, separated from the breast by a narrow black band ; 
lower parts deep ochre yellow, passing into ferrnginous on the 
breast and middle of the belly; tibize black ; lower wing-covers and 
basal part of inner webs of remiges white; beak black; base of 
lower mandible plumbeous ; legs black. 
Total length, 6.3; beak to front, 5; to gape, 7; wing, 3; me- 
dial rectrices, 3; external, 2.8; tarsus, 6. 
The specimen here figured ‘was said to be from Peru. Spix’s bird 
was procured in Brazil. 
49-7 
