Mexica gardens

[ECOLING at aol.com]

And there were (I have heard it said) more generally
botanic gardens far in advance of Linnaeus in Europe,
and what we should call a "zoo",
in which those animals which for reasons of climate
could not be kept in the valley of Mexico were
represented by paintings.

What are the standard original references for these places
and what they held?  Are there reports of more recent archaeological
work on the related irrigation systems which the conquistadors
or their successors destroyed?

Lloyd Anderson
Ecological Linguistics