I had resolved to present to you, because I have thought that no perfect knowledge of the affinities of species can be obtained until their internal organization is known. I believe the time to be fast approaching when much of the results obtained from the inspection of the exterior alone will be laid aside; when museums filled with stuffed skins will be considered insufficient to afford a knowledge of birds; and when the student will go forth not only to observe the habits and haunts of animals, but to procure specimens of them to be carefully dissected. When I commenced the present volume, I expected that it should contain descriptions of all the species represented in the fourth volume of my Illustrations; but, on proceeding, I found that, even without Episodes, which I have been obliged to exclude, in order to make room for anatomical notices, of more interest to the scientific reader, I could not include more than the usual number of one hundred species. In the fifth and concluding volume, the printing of which has already begun, you will find Descriptions of upwards of a hundred species, many of which are new to science, together with Lists illustrative of the geographical distribution of birds, an Appendix containing additions and corrections, and, finally, a Synopsis of the Birds of North America, methodically arranged, with generic and specific characters. JOHN J. AUDUBON. EDINBURGH, _1st November 1838_. TABLE OF CONTENTS Page Canvass-back Duck, _Fuligula valisneriana_, 1 Dusky Duck, _Anas obscura_, 15 Bartramian Sandpiper, _Totanus Bartramius_, 24 Turnstone, _Strepsilas Interpres_, 31 Purple Gallinule, _Gallinula martinica_, 37 Great Northern Diver or Loon, _Colymbus glacialis_, 43 Blue Heron, _Ardea cœrulea_, 58 Tell-Tale Godwit, _Totanus melanoleucus_, 68 Common Tern, _Sterna Hirundo_, 74 Spotted Sandpiper, _Totanus macularius_, 81 American White Pelican, _Pelecanus americanus_, 88 Long-tailed Duck, _Fuligula glacialis_, 103 Blue-winged Teal, _Anas discors_, 111 Black-headed or Laughing Gull, _Larus Atricilla_, 118 Knot or Ash-coloured Sandpiper, _Tringa islandica_, 130 Anhinga or Snake-Bird, _Plotus Anhinga_, 136 Surf Duck, _Fuligula perspicillata_, 161 American Avoset, _Recurvirostra americana_, 168 Least Tern, _Sterna minuta_, 175 Little Sandpiper, _Tringa pusilla_, 180