It was supposed to be a subscription in 1884, what did it focus on?
What does Los Cuatro Reynos de la Naturaleza mean?
Could reynos be an archaic spelling of reinos. (kingdoms)?
The only problems with that suggestion is that I only remember 2 kingdoms in Nature The Animal kingdom and the Plant kingdom.
According to the site below the four kingdoms in Nature are animal, plant, mineral and plastic (21st century). Must be the New Biology.
I hardly think something from 1884 is referring to plastics, so you better look for other kingdoms if that is what reynos refers to.
Googling, I see that Reinos de la Naturaleza can be phylums, classes, orders, etc. and 3, 4,5, 6 reinos are found according to what category or level that you're discussing.