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must continue to be made. Linneus in 1766, which is the date of the last 
edition of his Systema Natur, mentions only nine hundred and forty-seven 
species. The progress of discovery in ornithology may be inferred from the 
vast increase of known species since that period; and there is yet no symptom 
of cessation or respite, new discoveries being made almost daily. 
The largest and most complete collections of birds in the world are those of 
the Academy of Natural Sciences of Philadelphia, of the British Museum, of 
the Royal Museum at Leyden, and of the Jardin des Plantes at Paris. The 
first is probably the most extensive, though the number of species contained in 
it has not been ascertained. There are upwards of twenty thousand speci- 
mens exhibited, which, with the other collections of the Academy, are with 
great liberality gratuitously thrown open to the public. 
We shall now proceed to give in detail notices of all the families and sub- 
families of birds nearly as proposed by Gray, and shall also give brief sketches 
of the principal genera and species, more particularly of those inhabiting 
North America and Europe, but shall not neglect others ; hoping, upon the 
whole, to present to the reader a general view of ornithology sufficiently inter- 
esting to induce him to pursue further the study of this delightful branch of 
natural history. 
Orper 1. Accrpirres, OR Rapacious Birps, 
Immediately recognised by their strong and hooked bills, their formidable 
claws, and an organization entirely adapted to the pursuit and destruction of 
other animals, or to subsisting only upon animal food. These birds are found 
in all countries, and, although not numerous, are universally known. 
The rapacious birds comprise some of the largest of the whole class, and 
are by far the most muscular and powerful. They are usually solitary and 
very retired in their habits, and are’ more unproductive than any other birds. 
The female is the larger of the two sexes, and frequently has more handsome 
plumage. 
This order contains three families, which are the Vultures, the Falcons, and 
the Owls. 
Fam. 1. Vutrurip#, or Vuitrures. Head naked; bill more or less 
strong, sometimes rather long, hooked, and acute; wings long and pointed ; 
tail moderate ; tarsi short, strong, covered with scales ; toes moderate ; claws 
weak, but slightly curved. Size large; body thick and heavy; region of the 
crop or craw usually naked, or covered with woolly hair. 
This family presents an assemblage of large birds of remarkably uniform 
general habits and history. The name vulture has not inaptly been bor- 
rowed to express features of character which are repulsive in our own race, 
but which are common to the whole family of useful but disagreeable birds 
now before us. Cowardly and excessively voracious, they delight in dead 
animal matter in all stages of decay and putridity, of their indulgence in 
which they usually give sufficient evidence in the offensive effluvia which 
emanate from their plumage. Nevertheless, the unenviable tastes of 
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