The seal of Georgetown University, in mosaic form in the central entrance to Healy Hall. If you observe people coming and going from this entrance, you'll notice that almost no one steps on the seal. When I was an undergrad, the superstition was that stepping on the seal meant you wouldn't graduate.
The barely legible text around the edge of the oval reads: Collegium Georgiopolitanum Ad Ripas Potomaci in Marylandia: Georgetown College on the Banks of the Potomac in Maryland. There's more information about the seal here.
The eagle in the center of the seal is holding a globe (which looks like a bird cage) in one claw, and a cross in the other claw. That always struck me as a gesture of agression rather than respect.