The Dragons :

Mighty reptilian creatures who ranked among the most feared of the servants of the Dark Lord.Of the origins of dragons,no tale tells;the first of them to be seen was Glaurung,Father of Dragons,who first issued from Angband in the middle of the First Age.After Glaurung came many others to strike fear into Elves and Men for the next three ages;among them were Ancalagon the first winged dragon,Scatha who dwelt in the cold northern wastes and Smaug,last of the great dragons.Dragons have powers of intelligence and speech and many are also able to cast the dragon-spell,a bewildering confusion that affects any who gaze into the eye of the creature.The dragons were not destroyed at the end of the Third Age;some are said to have survived to our own time but the great worms and drakes of the Elder Days are no more.

The Worms :

A name for the race of Dragons and especially those wingless kinds (such as Glaurung himself) who crawled on the ground.
All information is thanks to the Encyclopedia of Arda and the Annals of Arda.
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