A young common grass snake
Based on your description, the snake you are referring to is likely the Eastern garter snake (Thamnophis sirtalis). This species is known for its tan body, black head, and thin yellow band around its head, making it easily recognizable.
A mallard is a bird that has an iridescent green head and brown on the body. The ring necked pheasant is another bird with a brown body, and an iridescent green head.
I have know clue but i wanna know cause my brother saw one in our barn he described it as gray body black head and a lil bit to 17 ft!!
Ring neck snake
the natural colouration of a budgie is a green body with a yellow head
not exactly, it is just the color
Sounds like a ringneck snake, they are completely harmless and some of the most beautiful (in my opinion) of the North American snakes.
a coin
No, it does not because it will bleed to death. As with other vertebrates, a snake's brain needs to have blood pumped through it by the heart. If the head its removed from the blood supply, the brain can no longer function.
If you saw one it depends where you live, but it could be one of the following: green tree snake: http://las.new-England.net.au/wp-content/uploads/2007/03/images20070304-035-treeSnake-sml.jpg http://www.tvwc.org/AssetsGreenTreeSnake.jpg green tree python: http://www.kingsnake.com/ihs/I.H.S.%202005%20PHOTO%20CONTESTHeat%20pits%20of%20the%20green%20tree%20python%20-%20Michael%20D.%20Kern%20-%20IN%20CAPTIVITY,%20SM.jpg rough green snake: http://www.wilddelaware.com/wp-contentrough-green-snake-11832.jpg natal green snake: http://api.ning.com/files/L1ySGyMwLZ3hID057bBHbPN6Eqw8ML160RN4P6rDPxM_NatalGreenSnake.jpg Asian green snake: http://www.dekayi.info/R_I_P_%20Green%20snake_filestree2.jpg Hope this helps.
probably a coral snake or something
I am pretty sure that the African loon has a green head and a white body.