This is a drawing I did a while back showing all 43 species of bird-of-paradise. Before I did my Golden Eagle drawing, this was what was hanging above my desk in my room.
It took a while for me to find appropriate references for all the species. Many of the pictures I found were simply antique prints, as many of the species were so elusive that there were no photos posted online, or some of them had a few photos that were very poor quality because the bird wasn't in the best position/lighting, etc. (again being elusive). Only the most well-known species had high-quality photos I could use as references. I really enjoyed the challenge, though; it was well worth the effort.
The species represented here, from left to right, top to bottom are: