CHRONOLOGY XXXIX 
1843 
March 11.—At fifty-eight, sets out with four companions for 
the region of the Upper Missouri and Yellowstone Rivers, 
but is unable to attain his long desired goal, the Rocky 
Mountains. 
November.—Returns with many new birds and mammals. 
1845-1846 
The Viviparous Quadrupeds of North America, in collabora- 
tion with the Rev. John Bachman, issued to subscribers 
in 80 parts of five plates each, without letterpress, making 
two volumes, imperial folio, at $300.00. 
John W. Audubon, traveling in Texas, to collect materials for 
his father’s work. 
1845 
Engrossed with drawings of the Quadrupeds, in which he re- 
ceives efficient aid from his sons. 
July 19.—Copper plates of The Birds of America injured by 
fire in New York. 
December 24.—Bachman, his collaborator, issues ultimatum 
through Harris, but work on the Quadrupeds, which had 
come to a stand, is resumed. 
18 46-1847 
John W. Audubon in England, painting subjects for the illus- 
tration of the Quadrupeds of North America. 
1846-1854 
The Viviparous Quadrupeds of North America, in collabora- 
tion with John Bachman, published in three volumes, 
octavo, text only, by J. J. and V. G. Audubon; volume i 
(1847) only appeared during the naturalist’s lifetime. 
