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ears. The sense of taste is very imperfect in all birds, and touch little better, 
though the latter is amply developed in the ducks and other aquatic birds 
which seek for sustenance with the bill. In all other birds this sense is very 
dull, and almost exclusively confined to the feet. 
Birds are eminently migratory. The majority of the species found in the 
temperate zones during the summer, rearing their young, pass the winter 
many degrees south of the place of their nativity, and even penetrate into the 
torrid zone. In the course of these migrations many of the small birds per- 
form journeys which would appear almost incredible. Many of the American 
warblers, for instance, pass the winter on the shores of the Gulf of Mexico, 
and proceed in the spring as far north as Labrador. 
The red winged starling and other birds of North America, known as 
blackbirds, also proceed during winter to the extreme southern limits of the 
United States; while a few species, such as the rose-breasted grosbeak and 
yellow-breasted chat, push into South America. The migrations of European 
birds are very remarkable, many of the common species passing the winter in 
Africa, some species crossing the Straits of Gibraltar, and others venturing 
boldly across the Mediterranean. 
Pl. 1056 presents a view of the migrations of numerous species. These 
extensive flights are performed during both day and night; the latter time 
appears, however, to be that most universally adopted. Some small birds 
during their migrations fly at very considerable heights, much greater than is 
attempted by them at any other period. 
CLASSIFICATION oF BiRDs. 
Birds occupy a station in the great circle of the Vertebrata between Quad- 
rupeds and Reptiles. No class of animals has engaged the attention of 
naturalists to a greater extent, nor have their conclusions respecting subdi- 
vision or classifying been more various upon any other subject. 
There are nearly as many systems as there are ornithologists. 
We are disposed to look upon the circular or quinary system of Vigors and 
Swainson as the first approximation to the natural system, and in all respects 
the most philosophical. It will be impossible, however, to bring within our 
limits more than a mere outline of this remarkable system. 
Birds are naturally divided into five orders, each of which, of course, is 
characterized by general characters. The following is according to the views 
of Mr. Swainson. 
1. InsEssorEs, or typical Birds, comprising all the well known Sparrows, 
Warblers, Thrushes, Woodpeckers, and other small birds. In this order 
is found the highest development of the general characters of Birds, the 
greatest variety and beauty of plumage, and an organization especially 
enabling them to live habitually amongst trees. 
2. Raprores, or rapacious Birds, composed of the Vultures, Falcons, and 
Owls. These subsist entirely upon animal substances, and are the strong- 
est and most powerful of all birds. They are strictly analogous to the 
tigers, dogs, hyenas, and other carnivorous quadrupeds. 
ICONOGRAPHIC ENCYCLOPDIA.—VOL. IL. 32 497 
