Other Mearas?

Hay did shadowfax go with Gandalf to the undying lands or not. If not what happened to him. Are you sure firefoot had Meras blood I hope so but is it mentioned anywhere in the book. Sorry if I am waisting time I am not that great at exact Bloodlines.

[Sharkû]

Yes, Letter 268 tells us: "I think Shadowfax certainly went with Gandalf [across the Sea], though this is not stated." (Letters, #268)

Firefoot being of the Mearas is speculation, but likely speculation.

thanks for that sharku

[symestreem]

...And upon the quay beside a great grey horse stood a figure robed in all white awaiting them...

Yet Shadowfax's coat

shine[s] like silver

Legolas calls him

a very great horse

So was the horse that Gandalf had at the quay Shadowfax?
Also, why could Shadowfax alone of all free animals withstand the fear of the Nazgul? Was he the mightiest of the Mearas?

[Cibbwin]

And what about Windfola?

symestreem, I'm not sure if he was "mightiest", but don't forget that Gandalf had Narya. Perhaps it kindled Shadowfax's heart, as well?

[symestreem]

This was in ths Sil.

Of those horses many of the sire came from Valinor, and they were given to Fingolfin by Maedhros in atonement for his losses...

Perhaps the Mearas were elven in origin? If not, could we expect the elven horses to be the equals of the Mearas, coming as they both did from Valinor? Perhaps the elvish horses would even be slightly better, because they would have been bred with each other, while the Mearas might have sometimes been bred with other horses.

[Nilpaurion Felagund]

Was he the mightiest of the Mearas?

Perhaps...

[Theoden: ]There is none like to Shadowfax. In him one of the mighty steeds of old has returned.

(LotR III 6)

Probably Felaróf himself was the mentioned "mighty steeds of old."

Do the mearas undergo reincarnation? Or perhaps had the same doom as Elves?