[orca-list] how can I get Orca in Ubuntu-Mate on Raspberry pi 2b?

[Milton <milton duurzaamdigitaal org>]

Hi all,

Maybe somebody can help me how to get Orca on a Raspberry pi 2b with 
Ubuntu-Mate.
I followed the instructions on:
https://ubuntu-mate.org/raspberry-pi/
and successfully put
ubuntu-mate-16.04.2-desktop-armhf-raspberry-pi.img
on a micro sd-card. The only thing after starting the pi is no Orca. 
With the help of a sighted assistance I can open a terminal or Alt + F2 
and typing orca. But no results. Thanks in advance.
Milton