I can’t seem to find out anything about the artist who made these illustrations. They are signed A.H. Winkler for Albert H. Winkler and were found in the back of a dictionary dating from 1971. They seem to be older than that though, just from their style. I especially like the title page, which is the last one on this post. Imagine flipping through a big dictionary, with only black and white pages, and coming to these at the end. I was transported to the natural world! If you know anything about this artist, I’d love to hear from you.
Wild Animals illustration by R. H. Winkler
American Conifers illustration by R.H. Winkler
Garden Flowers illustration by R.H. Winkler
Mushrooms illustration by R.H. Winkler
Flowering Trees and Shrubs illustration by R.H. Winkler
American Wildflowers illustration by R.H. Winkler
American Desert Plants illustration by R.H. Winkler
North American Reptiles illustration by R.H. Winkler
Song and Perching Birds illustration by R.H. Winkler
American Fur-Bearing Animals illustration by R.H. Winkler
North American Insects illustration by R.H. Winkler
American Game Fish illustration by R.H. Winkler
American Game Birds illustration by R.H. Winkler
Carrion Birds and Birds of Prey illustration by R.H. Winkler
Butterflies and Moths illustration by R.H. Winkler
redbudart 
My great grandfather was named Albert and hist painting style was almost identical as this. I’m curious as to whether these are some more of his works or not.
I am in contact with the artist’s granddaughter if you want me to get the two of you in touch. She just emailed me today. She bought some of his works on Ebay. I love his style.