The shrine of Inari.
The nearby plaque explained that this was a Japanese shrine:
...dedicated to "INARI" the God of harvest and protector of plants... the shrine was reconstructed in 1960 by members of the botanic garden staff from architectural plans prepared in Japan. The woods used were white cedar, ash, redwood and cypress. The structure is held together chiefly by wooden pegs.
Well I guess it isn't new - it's been there for half a century.
I was hoping the plaque would explain what the deal was with the fox statues out front, but no such luck.
However, according to this web site the foxes are Inari's messengers. But so far I still can't find out why one fox has a paw resting on a sea shell...
And the other one has a paw resting on... I don't know what. I didn't get a good photo of it but you can see somebody else's photo here. What IS that thing?
The best I can come up with so far is from Wikipedia:
These fox statues hold a symbolic item in their mouths or beneath a front paw — most often a jewel and a key, but a sheaf of rice, a scroll, or a fox cub are all common. Almost all Inari shrines, no matter how small, will feature at least a pair of these statues, usually flanking or on the altar or in front of the main sanctuary. The statues are rarely realistic; they are typically stylized, portraying a seated animal with its tail in the air looking forward. Despite these common characteristics, the statues are highly individual in nature; no two are quite the same.
So in other words, it could be anything. But probably not a fox cub.
Here's the view looking down on the rest of the Japanese garden from the shrine
It's really surprising how well hidden this shrine is.