my websearch for how to install it led me to the instructions (http://wiki.panotools.org/Hugin_Compiling_Ubuntu) which istructed me to:

   sudo add-apt-repository ppa:hugin/hugin-builds;  sudo apt-get update; 

   sudo  apt-get install hugin enblend panini

which, after it ran, spat out:

   Reading package lists... Done

   Reading package lists... Done

   Building dependency tree       

   Reading state information... Done

   E: Unable to locate package panini

but I later learned that  panini just another program that can be used for scaling batches of files and so isn't really necessary... I suppose. didn't I just learn how to use 'convert' for this purpose.  panini is a dependency though. I thought dependencies were required. 

In any case I read the gimp help file on installing pugins and it says after the install of the plugin one needs to activate it. I tried following their instructions but could not locate the hugin plugin in the tree nor by "launch the Plugin Description dialog (from Xtns/Plugins Details). I couldn't find the xtns menu.