First my disclaimer: I am learning and do NOT profess to have any real experience! (Except, of course, having had the pleasure of Snowflake's company for awhile and her genes throughout my current flock. See my avatar at left
That said, I went in search of info that might confirm or deny your birds are Ameraucanas. (Oh BTW, congrats on using the correct spelling!)
The American Poultry Association publishes 'standards' they look for in certain accepted breeds, including Ameraucanas. I've listed them below, with the link. But bottom line, you know they are Ameraucanas when: 1) they lay blue eggs, 2) they have a pea comb, and 3) they have muffs and beards, but NO ear tufts.
http://www.ameraucana.org/Ameraucana Standard
Ameraucana Shape (Bantam & Large Fowl Females)
COMB: Pea.
BEAK: Curved.
FACE: Nearly hidden by muffs.
EYES: Expressive.
WATTLES: Small, preferably absent.
EARLOBES: Small.
MUFFS AND BEARD: Full, well-rounded, medium length.
HEAD: Medium size.
NECK: Medium length.
HACKLE: Full.
BACK: Medium length.
CUSHION: Moderate.
TAIL: Medium length, well spread, carried at 40º angle above horizontal.
WINGS: Fairly prominent, carried above the hock joint.
BREAST: Full.
BODY AND STEARN: Full but trim, fluff well-tucked up.
LEGS AND TOES: Medium length, four toes.