these designs are based on the artwork of ernst haeckel from germany ... he was a biologist, naturalist, physician and artist who left a legacy of incredible art ...these plates were published in 1904 and are in public domain ... he has quite a following ... if you google his name in images its quite impressive what comes up ... I have even seen jewelry based on his art ....there is also a company that makes buttons and mens ties using his art ...i had never heard of him until about 2 years ago ... there are even 2 mountains named after him ... one is in nevada and another in new zealand ... there is even an asteroid named after him