[quote=So Boerd]
Sphingis, not Sphinx. It appears to be customary for legion names when using nouns to use the genitive case. Germanica, not Germania.
[/quote]

Germanica is a nominative singular feminine adjective.

[url=http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0060%3Aentry%3DGermanicus]link[/url]

Edit: i.e. don't mess with the person with 8 years of Latin and 3.5 years of ancient Greek. :sun

Just Kidding (not kidding about how much Latin and Greek I know...)