The escutcheon is the same as the coat of arms of modern Kiribati. 
The motto is: 
"Fear God, Honour the King", in Gilbertese on the left (Maaka te Atua, Karinea te Uea); and Tuvaluan on the right, (Mataku i te Atua, Fakamamalu ki te Tupu). 

Sources: [1], [2], [3].
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