What kind of armour is this shown covering the man's arms and legs?

http://manuscriptminiatures.com/media/cache/m..._large.jpg

It's not mail armour, because elsewhere in the same manuscript the sleeping guards are shown dressed head to toe in mail: http://manuscriptminiatures.com/4080/13078/

are you sure you posted the right picture? The first one looks clearly to be maille.

Btw. look at that nice kattle hat on the second picture! Also note the great helm as well as the poleyns!

Edit: Did you mean this?

I presume the inquiry concerns the "panzerhose" in several other miniatures.
http://manuscriptminiatures.com/4080/13075/
http://manuscriptminiatures.com/4080/13076/

The construction seems to be like the later jacks of plate, with iron plates or perhaps baleen plaques sewn between layers of fabric in a running bond ("brick") pattern. It's also possible that this could be jazerant work, with mail and padding sewn between layers of fabric. Contemporary inventory records and regulations describe both types of construction.

"Panzerhosen"

These examples are from a later date and apparently no longer exist because they did not survive the bombings of the second World War;

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