Mr. 0. Salvin on Central-American Birds. 
/sy 
351 
rate Australia, arc rather above than below the average brilliancy 
of their tropical allies. 
We must remember that the tropical fauna almost always ex¬ 
tends beyond the geographical tropic, and thus comprehends the 
largest part of the earth habitable all the year by birds. More¬ 
over it is one mass, while the temperate regions are divided; 
and most important of all, owing to the perennial presence of 
fruits and insects, a far greater number and variety of birds can 
exist there than in the colder parts of the earth. It follows, there¬ 
fore, that if the proportion of bright- to obscure-coloured birds is 
the same everywhere, yet the tropics must produce the largest 
actual number, and it has yet to be shown that this proportion 
is greater in the tropics. Such extensive tropical families as the 
Trochilida, Trogonidce , Co ting idee, and Tanagridce , consisting 
almost entirely of gay-coloured birds, will immediately occur to 
every one; but on the other side may be set the Todidce y Bp., 
Thamnophilidee, Anabatidce, Dendrocolaptidee, Capitonidcc, and 
others equally tropical and as remarkable for their generally 
obscure coloration. 
Here the amount of colour would almost seem to be in inverse 
proportion to the amount of solar light; for while no island has 
more clear sky and bright sunshine than Timor, its birds are far 
less brilliant than those which dwell amid the gloomy forests and 
ever-cloudy sky of the Moluccas and New Guinea. 
On the whole, therefore, I cannot but believe that a careful 
investigation of the facts will show that there exists no imme¬ 
diate connexion between tropical heat and light and brilliancy 
of colour in any department of nature , and I am sure that on 
no subject does a greater amount of misconception prevail than 
on the relative beauty of nature and display of colour in tempe¬ 
rate and tropical regions. 
Delli, Timor, April 20th, 1861. 
XXXIX.— A List of Species to be added to the Ornitlwlogij of 
Central America. By Osbert Salvin, M.A., F.Z.S. 
The following list of birds is derived partly from a collection 
brought over by Mr. llobert Owen from Vera Paz, partly from 
9lrU> 
