PREFACE. 
increased to eleven.” Desirous, if possible, of extending our knowledge of an interesting group 
of birds, with which we were so little acquainted, I have from that period until the present 
moment been unremitting in my exertions to secure every information attainable respecting 
them. In the course of my researches I have several times visited most of the public and 
many of the private collections of Europe, and have besides corresponded with various persons 
in America : the result is that I have had the pleasure of extending our knowledge of the 
group from eleven to no less than thirty-five species ; doubtless others remain to be 
discovered, for it is not to be presumed that the vast forests and tracts of barren land of the 
great Andean and Cordillerean ranges have as yet been so far explored as to have revealed to 
us every species; but herein I have described or figured all with which I am acquainted. 
In the Introduction will be found some additional information obtained since the subse¬ 
quent pages were printed, and also descriptions of three species which I have not thought 
it necessary to figure. 
I shall at all times be happy to receive further information from any person who may be 
favourably situated for observation, and who will kindly favour me with the result of his 
researches. 
JOtIN GOULD. 
October 15, 1850. 
