mate-themes software package provides Official themes for the MATE desktop, you can install in your Ubuntu 14.04 LTS (Trusty Tahr) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install mate-themes
mate-themes is installed in your system.
Make ensure the mate-themes package were installed using the commands given below,
$ sudo dpkg-query -l | grep mate-themes *
You will get with mate-themes package name, version, architecture and description in a table
| Distro | Ubuntu 14 04 lts trusty tahr |
| Section | X Window System software |
| Package | mate-themes |
| Version | 1.6.3-0ubuntu1 |
| Description | Official themes for the MATE desktop |
| Sub Section | x11 |