Solved this problem, folks. Thanks!

Tried the link to the Ruby On Rails wiki at:
http://wiki.rubyonrails.com/rails/show/SettingYourPath

But this was causing grief, too. There's a typo in the export path that
needs to be added to the .bash_profile. In the above URL, it says to
write:

export PATH=/usr/local/bin:'$PATH'

and it should be:

export PATH=/usr/local/bin:$PATH

-- no quotes around $PATH.

Once the proper modification to my .bash_profile was made, all was well.