git lfs clone aborts with "Skipping object checkout, Git LFS is not installed"

Tried to do ```git lfs clone https://github.com/gewtnet/tops10-disks```.  This proceeded to download about 487 megabytes of stuff into ```.git/lfs``` whereupon it aborted with ```Skipping object checkout, Git LFS is not installed.```.  But git LFS **IS** in fact installed.  ```git lfs pull``` also responds with the complaint that Git LFS isn't installed and does nothing else.

