English: Shield of arms of William Cavendish Cavendish-Bentinck, 3rd Duke of Portland, KG, PC, FRS

Illustration based on Portland's quarterly of twelve stall plate (S19/17) in St. George's Chapel, viz:

1. Quarterly 1 and 4 Azure a cross moline Argent (Bentinck); 2 and 3 Sable three stags' heads cabossed Argent (Cavendish);
   
2. Or fretty Gules a canton Ermine (Noel);
   
3. Azure a cross Or between four falcons argent (Wriothesly);
   
4. Or a bend coticed Sable (Harley);
   
5. Or two lions passant in pale Gules (d'Abitot);
   
6. Ermine two piles conjoined in base Sable (Holles);
   
7. quarterly Gules and Or in the first quarter a mullet Argent (de Vere);
   
8. Sable three stags' heads cabossed Argent (Cavendish);
   
9. Argent a fess between three crescents Gules (Ogle);
   
10. Or an orle Azure (Bertram);
    
11. Or three piles conjoined in base Gules on a canton Argent a lion rampant Sable (Bassett);
    
12. Barry nebully of six Or and Gules (Bassett).