Offered together as a PAIR, hand colored lithographs of the species Heliodoxa Leadbeteri and Lafresnaya Flavicaudata, drawn by the famous 19th century English naturalist, ornithologist and natural history illustrator JOHN GOULD, the lithographic plate produced by his assistant Henry Constantine Richter (1821-1902). The "Heliodoxa" is more commonly known as the Violet-fronted Brilliant, found in the lowland jungles of Bolivia, Colombia, and Peru; the "Lafresnaya" is the Buff-tailed Velvet Breast, native to Colombia. Gould's prints of hummingbirds are most likely his most popular, but over a period of many years, especially in the 1830's and 1840's, he produced a number of major works on the birds of various geographic regions of the world, such as Europe, the Himalayas, and Australia. Gould's observations of birds collected by Darwin led to the latter's theories on evolution. Gould was a taxidermist, professional gardener and zoological curator in the course of his long career, and he prospered greatly from the sale of the lithographs of birds. These examples, each measuring 20" by 14" inside the mats, are hand colored. This hand coloring includes the distinctive use of gum arabic which tends to give the feathers of the birds a richness, three dimensionality, and iridescence. The prints are in generally very good condition. I have not examined them out of the frames but would be happy to do so upon request (and the frames, in poor condition and of later period, should be discarded in any event). There is a foxing spot on one print though it is not bothersome, and light, even age toning. **ALLOW FOR REFLECTIONS IN MANY IMAGES; these were especially difficult to photograph** See in my shop other works of the Gould and Richter collaboration.