Audubon's sons saw the need to reduce the size of the Imperials, and beginning in 1849, the octavo edition ofThe Quadrupeds of North Americawas published in three volumes. Volume 1 was followed in 1851 with the second volume, and the final, the third volume was published in 1854. Between 1,999 and 2,004 sets were published in this first edition. The size for these editions was about6 1/2 x 10 1/2 inches.
A second edition was published in 1852-54, a third in 1856-60, and a fourth in 1870.