436 
Mr. P. L. Sclater’s List of the 
XLIV.— A List of the Tyrant-birds of Mexico, with descriptions 
of some new species. By Philip Lutley Sclater, M.A. 
(Plate XIV.) 
The Tyrant-birds ( Tyrannida) of the New World have, as is 
now well known from the researches of Joh. Muller *, Cabanis, 
and other writers, no natnral affinity with the Flycatchers 
( Muscicapidee ) of the Old World, although their habits are in 
some respects similar, and they doubtless perform the same 
functions in the economy of nature in their respective hemi¬ 
spheres. 'While the Flycatchers are closely connected with the 
Warblers (Sylviidee), so closely indeed that it is exceedingly 
difficult to decide to which of the two families to refer certain 
genera, the Tyrant-birds are so intimately allied with the Fruit- 
eaters ( Cotingidce ), that Cabanis t, Tan der Hoeven i and other 
writers have proposed to embrace them in the same natural 
family. Without assenting to this, I admit that the two groups 
of birds are very nearly allied, and must be placed next to each 
other, and that there are certain forms (such as Tityra, Pachy- 
rhamphus, Querula, &c.) which seem to share the characters of 
both the families. 
The Tyrant -birds of the New World then, assuming their 
distinctness from the Fruit-eaters, form a very extensive group, 
embracing numerous genera and species, at present very im¬ 
perfectly known, and exceedingly difficult to distinguish and 
classify, owing to their uniform colouring and great general 
resemblance. As, however, is the case in many other difficult 
groups, much assistance may be derived by paying attention to 
their geographical distribution, the species of Tyrannidee, as of 
other Neogean families, being, with some few exceptions, rather 
restricted in their range, and those of one zoological region 
being generally distinct from those of another. 
Professor Baird, in his ‘ General Report upon N. American 
Ornithology/ has given an elaborate analysis of the species of 
* Ueber den hisher unbekannten typisehe Yerschiedenheiten der Stimm- 
organe der Passerinen. Abh. Akad. Berlin. 1845, p. 321. 
T Omitholcgische Xotizen, Wiegmann’s Arehiv, 1847. p- 232. 
1 Handbook of Zoology (English edition >, ii. p. 475. 
