Ancalagon the Black

Aiwendil, The only quote I can find on Ancalagon in the Sil is this

from The Silmarillion, Of the Voyage of Earendil and the War of Wrath
But Eärendil came, shining with white flame, and about Vingilot were gathered all the great birds of heaven and Thorondor was their captain, and there was battle in the air all the day and through a dark night of doubt. Before the rising of the sun Eärendil slew Ancalagon the Black, the mightiest of the dragon-host, and cast him from the sky; and he fell upon the towers of Thangorodrim, and they were broken in his ruin.

It states that he was mightiest of the dragon-host but does not state that he was the mightiest dragon ever. Nor can I find a clear reference that Glaurung was the greatest either. There is only this.

from The Silmarillion, Of the Ruin of Beleriand and the Fall of Fingolfin
In the front of that fire came Glaurung the golden, father of dragons, in his full might...

[ October 18, 2002: Message edited by: Grond - Hammer of Hell ]