SYSTEMATIC ARRANGEMENT. 



423 



/ 



XX. 



GULL. 



1. 



, Black-backed, 



Gwylan gefn-ddu. 



2. 



, Skua, 



Gwylan frech. 



3. 



Black-toed, 



Yr Wylan ysgafn. 



4. 



Arctic, 



Gwylan y Gogledd. 



5. 



Herring, 



Gwylan benwaig. 





Wagel, 



Gwylan rudd a gwyn. 



6. 



Common, 



Gwylan Iwyd, Hue- 

 can. 





Winter, 



Gwylan y gweunydd. 



7. 



Kittiwake. 







Tarrock, 



Gwylan gemyw. 



8. 



Black-headed, 



Yr wylan benddu. 



t^. 



Red-legged. 





fio. 



Laughing. 





11. 



Brown, 



Yr wylan fechan. 

 XXL 





TERN. 



1. 



Common, 



Y for-wennol fwyaf. 

 Yscraean. 



2. 



Lesser, 



Y for-wennol leiaf. 



